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56-459: The tabia occupies an elongated ridge between the gorges of Upper Tanqwa and Tsech'i Rivers . The highest peak is near Aregen village (2,660 m (8,730 ft) a.s.l.) and the lowest place at the confluence of the two rivers (1,897 m (6,224 ft) a.s.l.). From the higher to the lower locations, the following geological formations are present: The main geomorphic units, with corresponding soil types are: The rainfall pattern shows

112-762: A Palaeozoic planation surface , that extents to the north and west of the Dogu'a Tembien massif. Subsequently, there was the deposition of sedimentary and volcanic formations, from older (at the foot of the massif) to younger, near the summits. From Palaeozoic to Triassic , Dogu’a Tembien was located near the South Pole. The (reactivate) Precambrian extensional faults guided the deposition of glacial sediments ( Edaga Arbi Glacials and Enticho Sandstone ). Later alluvial plain sediments were deposited ( Adigrat Sandstone ). The break-up of Gondwana ( Late Palaeozoic to Early Triassic ) led to an extensional tectonic phase , what caused

168-409: A pronaos (1960s), the rock church has cruciform columns, flat beams and a flat ceiling, a single arch, and a flat rear wall without apse. Windows give light to the church itself. Emperor Yohannes IV was baptised in this church. The Yohannes rock church at Debre Sema’it ( 13°34.62′N 39°2.24′E  /  13.57700°N 39.03733°E  / 13.57700; 39.03733 ) is located in

224-405: A 50 to 100 times larger discharge than the preceding baseflow . These flash floods mostly occur during the evening or night, because the convective rain showers occur in the afternoon. Evidence given by Italian aerial photographs of the catchment, taken in the 1930s show that 63% of the catchment was covered with woody vegetation (against 32% in 2014). This vegetation could slow down runoff and

280-609: A 70-metres long horizontal gallery, holds underground springs. Numerous other unexplored cave entrances are visible in Antalo Limestone cliffs. Like several other districts in Tigray , Dogu'a Tembien has a number of rock-hewn churches . These have literally been hewn from rock, mainly between the 10th and 14th centuries. The almost inaccessible Dabba Selama monastery ( 13°41.67′N 39°6.03′E  /  13.69450°N 39.10050°E  / 13.69450; 39.10050 )

336-519: A cluster of trees. The church was established in widened caves of the tufa plug. Just outside the district, on the western slopes of the Dogu’a Tembien massif, there are seven other rock churches. Mika’el Samba ( 13°42.56′N 39°6.81′E  /  13.70933°N 39.11350°E  / 13.70933; 39.11350 ) is a rock church hewn in Adigrat Sandstone . It holds grave cells off

392-516: A continuous hipped ceiling to the centre aisle. There are carved diagonal crosses as well as a cross carved above the arch into the sanctuary. The ceiling holds longitudinal beams that form a continuous lintel, which is similar to traditional Tigrayan workmanship. The church is at risk of collapse and hence access is not permitted. The Kidane Mihret rock church of Addi Nefas ( 13°33.3′N 39°1.44′E  /  13.5550°N 39.02400°E  / 13.5550; 39.02400 ) in Adigrat Sandstone

448-506: A few phonolite plugs in Dogu’a Tembien. The present geomorphology is marked by deep valleys, eroded as a result of the regional uplift. Throughout the Quaternary deposition of alluvium and freshwater tufa occurred in the valley bottoms. In Dogu’a Tembien, there are two main fossil-bearing geological units. The Antalo Limestone ( upper Jurassic ) is the largest. Its marine deposits comprise mainly benthic marine invertebrates . Also,

504-557: A few orange or lemon trees. Grivet monkeys are common and prevent growing of bananas. At several places, people have excavates caves in the sandstone. The larger ones, and most known are the TPLF caves in Addi Geza'iti . Here, in the 1980s, the party established underground rooms and offices cut out in sandstone cliffs, the TPLF carried out its political activities, including a major land reform; it

560-517: A natural cave of 20 metres by 20 metres. The roof of the cave is covered with sooth, evidencing the fact that the villagers took cover here, during the Italian bombardments of the Tembien battles in the mid-1930s. The Kidane Mihret rock church at Ab’aro ( 13°44.5′N 39°12.06′E  /  13.7417°N 39.20100°E  / 13.7417; 39.20100 ), is surrounded by tufa plugs, springs and

616-507: A slope gradient of 25 metres per kilometre. With its tributaries, the river has cut a deep gorge. Tributaries, upstream from Abiy Addi , include The runoff footprint or annual total runoff volume is 41 million m³ at the bridge in Abiy Addi and 79 million m³ at the confluence with Giba River at Barashuwa. Peak discharges up to 543 m³ per second occur in the second part of the rainy season (month of August) when there are strong rains and

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672-492: A small church is behind a waterfall 100 meters high. The Dabo Zellelew cave in Aregen at a height of about 2000 metres, has been explored over 14.4 m but its distance is claimed to be way longer ( 13°37′19″N 39°01′59″E  /  13.621862°N 39.033077°E  / 13.621862; 39.033077 ). It contains lithic tools, potsherds, engravings and paintings of Pastoral Neolithic age. The Mihdar Ab’ur cave in

728-535: A very high seasonality with 70 to 80% of the annual rain falling in July and August. Mean temperature in Addi Gotet is 18 °C, oscillating between average daily minimum of 10 °C and maximum of 25.7 °C. The contrasts between day and night air temperatures are much larger than seasonal contrasts. As there are no permanent rivers, the presence of springs is of utmost importance for the local people. The main spring in

784-433: Is a rather primitive rock church, protected from the weather by a pronaos that surrounds the entrance. The church comprises two circular well-carved cells that are used for baptisms. Above the sanctuary there is a series of small blind arcades. Beside the ancient church, a new cave is under excavation. Down from the church there are irrigated tropical gardens. Under cover trees, farmers grow coffee , local hops ( gesho ), and

840-409: Is also an ancient rock-hewn church in freshwater tufa , and still in use. The church of Kurkura Mika’el ( 13°40′N 39°9′E  /  13.667°N 39.150°E  / 13.667; 39.150 ), in a very scenic position in a small forest behind limestone pinnacles, is some 30 years old ( File:Antalo Limestone at Kurkura.jpg ). Behind it, the remnant of the earlier church established in

896-464: Is assumed to be the first monastery established in Ethiopia, by Saint Frumentius . The intrepid visitor will climb down, then scramble over narrow ledges along precipices, and finally climb an overhanging cliff. The mesa also comprises a church hewn in Adigrat Sandstone , in shape of a small basilica . The carvers attempted to establish four bays as well as with a recess . The pillars are rounded (which

952-416: Is common at tropical latitudes, the contrasts between day and night air temperatures are much larger than seasonal contrasts. The rainfall pattern, however, shows a very high seasonality with 70 to 80% of the annual rain falling in July and August. The annual seasons are “hagay” (dry season in winter), “belgi” (spring rains), “kremti” (main summer rains) and “qew'i” (autumn), when the crops are ripening off. In

1008-552: Is composed of the original population with a certain admixture of descendants of slaves and serfs who were brought from southwestern Ethiopia, and were in the service of bigger land owners during feudality. There is no formal discrimination , and all have adopted Tigrinya language and identify as Tigrayans today. However, when it comes to marriage, in-laws may informally verify the ancestry of bride or groom. Dogu’a Tembien comprises 24 tabias or municipalities (status 2019), which have been mapped with their boundaries: Based on

1064-652: Is dominated by farmlands which are clearly demarcated and are cropped every year. Hence the agricultural system is a permanent upland farming system . The farmers have adapted their cropping systems to the spatio-temporal variability in rainfall. The Dabo Zellelew cave at the west of Aregen at a height of about 2000 metres, has been explored over 14.4 m but its distance is claimed to be way longer ( 13°37′19″N 39°01′59″E  /  13.621862°N 39.033077°E  / 13.621862; 39.033077 ). It contains lithic tools, potsherds, engravings and paintings of Pastoral Neolithic age. The Mihdar Ab’ur cave in

1120-449: Is hewn in Tertiary silicified limestone , high up near the top to of the mountain. As a roof, a thin covering basalt layer was ingeniously used. The columns have a slightly cruciform plan and hold bracket capitals . Itsiwto Maryam rock church ( 13°40′N 39°1′E  /  13.667°N 39.017°E  / 13.667; 39.017 ) is hewn in Adigrat Sandstone . The church has

1176-611: Is in an apse. The sophisticated plan comprises a central axis and two open courtyards that cut deep into the rock. The newly hewn Medhanie Alem rock church in Mt. Werqamba ( 13°42.86′N 39°00.27′E  /  13.71433°N 39.00450°E  / 13.71433; 39.00450 ) is in a central, smaller peak (in Adigrat Sandstone ). Northwest of Abiy Addi , the Geramba rock church ( 13°38.84′N 39°1.55′E  /  13.64733°N 39.02583°E  / 13.64733; 39.02583 )

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1232-599: Is named in part after the former province of Tembien . Nowadays, the mountainous district is part of the Southeastern Tigray Zone. The administrative centre of this woreda is Hagere Selam . Dogu’a Tembien holds numerous prehistoric sites, which have been dated to the Middle Stone Age in Ayninbirkekin , or Pastoral Neolithic in Aregen and Menachek . The lowest places are where the main rivers leave

1288-476: Is transported by this river amounts to 596,000 tonnes per year. Median sediment concentration in the river water is 3.95 grammes per litre, but may go up to 68 g/L. The highest sediment concentrations occur at the beginning of the rainy season, when loose soil and dust is washed away by overland flow and ends up in the river. As such water contains many nutrients (locally it is called “aygi”), farmers estimate that it strengthens their cattle, which they will bring to

1344-513: Is uncommon) and expand at either end, supporting arches that appear as triangles. Women are not allowed to do the ascent, nor to visit monastery or church. Independently from the difficult access to the monastery, the surrounding sandstone geomorphology is unique. The Amani’el church in May Baha ( 13°40′N 39°5.4′E  /  13.667°N 39.0900°E  / 13.667; 39.0900 ) has also been carved in Adigrat Sandstone . Behind

1400-898: The Tertiary lacustrine deposits , interbedded in the basalt formations, contain a range of silicified mollusc fossils. In the Antalo Limestone : large Paracenoceratidae cephalopods ( nautilus ); Nerineidae indet.; sea urchins ; Rhynchonellid brachiopod ; crustaceans ; coral colonies ; crinoid stems. In the Tertiary silicified lacustrine deposits : Pila (gastropod) ; Lanistes sp.; Pirenella conica ; and land snails ( Achatinidae indet.). All snail shells, both fossil and recent, are called t’uyo in Tigrinya language , which means ‘ helicoidal ’. The vast areas with outcropping Antalo Limestone hold numerous caves. At Zeyi ( 13°33′N 39°9′E  /  13.550°N 39.150°E  / 13.550; 39.150 ),

1456-584: The karst aquifer . The large resurgence in Rubaksa ( 13°35′N 39°14′E  /  13.583°N 39.233°E  / 13.583; 39.233 ) irrigates an oasis in a dry limestone gorge. At Inda Mihtsun ( 13°33′N 39°21′E  /  13.550°N 39.350°E  / 13.550; 39.350 ), the May Bilbil resurgence is inside the bed of the Giba River; in the dry season spring water surges through

1512-603: The tabia is Gubarne in Kelkelay. In this area with rains that last only for a couple of months per year, reservoirs of different sizes allow harvesting runoff from the rainy season for further use in the dry season. The tabia centre Addi Gotet holds a few administrative offices, a health post, a primary school, and some small shops. There are a few more primary schools across the tabia . The main other populated places are: The population lives essentially from crop farming, supplemented with off-season work in nearby towns. The land

1568-411: The tabia : In the main villages, there are traditional beer houses ( Inda Siwa ), often in unique settings, which are a good place for resting and chatting with the local people. Most renown in the tabia are The main road Mekelle – Hagere Selam – Abiy Addi runs just east of the tabia . In Maygua there are regular bus services to these towns. Further, a rural access road links Addi Gotet to

1624-479: The 2007 national census conducted by the Central Statistical Agency of Ethiopia (CSA), this woreda had a total population of 113,595, an increase of 28% over the 1994 census, of whom 56,955 were men and 56,640 women; 7,270 or 6.4% were urban inhabitants. A total of 25,290 households were counted in this woreda, resulting in an average of 4.5 persons per household, and 24,591 housing units. The majority of

1680-585: The catchment. In the uppermost stretches of the river, only rock fragments of the upper lithological units will be present in the river bed, whereas more downstream one may find a more comprehensive mix of all lithologies crossed by the river. From upstream to downstream, the following lithological units occur in the catchment. During its course, this river passes through nine municipalities and three woredas and constitutes six different borders. From upstream to downstream: Trekking routes have been established across and along this river. The tracks are not marked on

1736-415: The catchment. On other steep slopes, exclosures have been established; the dense vegetation largely contributes to enhanced infiltration , less flooding and better baseflow . Physical conservation structures such as stone bunds and check dams also intercept runoff. The valley bottoms in the gorges of this river have been identified as a transhumance destination zone. Transhumance takes place in

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1792-508: The census; 6% of the urban and 2.4% of the total had toilet facilities. As of 2020, Dogu'a Tembien's territory belongs to the following new woredas: The East African Orogeny led to the growth of a mountain chain in the Precambrian (up to 800 million years ago or Ma), that was largely eroded afterwards. Around 600 Ma, the Gondwana break-up led to the presence of tectonic structures and

1848-591: The district. They are often located not far from the highest points, what indicates the magnitude of the relief Since ages, major footpaths and roads in Dogu’a Tembien have been using mountain passes, called ksad , what means “neck” in Tigrinya language . Place names show that the Tembien Tigrayans or Tembienot were partly Agew in the past; still nowadays, there are Agew speakers in Abergele , directly southwest of Dogu’a Tembien. The population of Dogu’a Tembien

1904-560: The future, but decreased spring rains. About three quarters of Dogu’a Tembien (800 km ) drains to Giba River , and the remaining quarter (240 km ) to the Weri’i River . The general drainage is westward, to the Tekezze River. Main tributaries in Dogu’a Tembien, from upstream to downstream, are At the lower part of the Antalo Limestone , where it lies on the Adigrat Sandstone , there are high discharge resurgences that drain

1960-471: The ground but can be followed using downloaded .GPX files. In the rainy season, flash floods may occur and it is advised not to follow the river bed. Frequently, it is then also impossible to wade across the river. Degua Tembien Dogu'a Tembien ( Tigrinya : ደጉዓ ተምቤን , "Upper Tembien", sometimes transliterated as Degua Tembien or Dägʿa Tämben ) is a woreda in Tigray Region , Ethiopia . It

2016-460: The inhabitants said they practiced Ethiopian Orthodox Christianity , with 99.89% reporting that as their religion. The 1994 national census reported a total population for this woreda of 89,037, of whom 44,408 were men and 44,629 were women. The largest ethnic group reported in Dogu'a Tembien was the Tigrayan (99.87%). Tigrinya was spoken as a first language by 99.89%. Concerning education , 7% of

2072-506: The lowering of large parts of the Horn of Africa . As a consequence a marine transgression occurred, leading to the deposition of marine sediments ( Antalo Limestone and Agula Shale). At the end of the Mesozoic tectonic phase, a new ( Cretaceous ) planation took place. After that, the deposition of continental sediments ( Amba Aradam Formation ) indicates the presence of less shallow seas, what

2128-487: The main asphalt road. Its mountainous nature and proximity to Mekelle makes the tabia fit for tourism. The high variability of geological formations and the rugged topography invites for geological and geographic tourism or "geotourism". Geosites in the tabia include: Trekking routes have been established in this tabia . The tracks are not marked on the ground but can be followed using downloaded .GPX files. The facilities are very basic. One may be invited to spend

2184-401: The main church, there are elongated chambers, maybe been the beginnings of an ambulatory . To enter the church, one has to go down a few. Remarkably, at the entrance, a pool of water is fed by a spring. The Welegesa church ( 13°43′N 39°4′E  /  13.717°N 39.067°E  / 13.717; 39.067 ) is hewn in Adigrat Sandstone . The entrance to the church is part of

2240-484: The main space. As Mika'el Samba is not a village church, priests are only present on the monthly Mika’els day, the twelfth day in the Ethiopian calendar . The Maryam Hibeto rock church ( 13°42.67′N 39°6.44′E  /  13.71117°N 39.10733°E  / 13.71117; 39.10733 ) is located at the edge of a church forest. It is hewn in Adigrat Sandstone , with a pronaos in front of it. On both sides of

2296-474: The monumental Zeyi Abune Aregawi church holds the entrance to Northern Ethiopia's largest cave. The 364-metres long oval gallery displays stalactites , stalagmites , decametre-high columns, bell-holes following joints, and speleothems on walls and floor. The 145-metres long Zeleqwa horizontal gallery is located in a cliff nearby the river of the same name ( 13°38′N 39°7′E  /  13.633°N 39.117°E  / 13.633; 39.117 ). At

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2352-536: The night in a rural homestead or ask permission to pitch a tent. Hotels are available in Hagere Selam and Mekelle . Tanqwa The Tanqwa is a river of northern Ethiopia . Rising in the mountains of Dogu’a Tembien (2510 metres above sea level), it flows westward to Giba River which empties finally in the Tekezé River . It is a confined river, locally meandering in its narrow alluvial plain, with

2408-455: The population were considered literate, which was less than the Zone average of 14%; 8% of children aged 7–12 were in primary school; 0.14% of the children aged 13–14 were in junior secondary school, and 0.21% of the inhabitants aged 15–18 were in senior secondary school. Concerning sanitary conditions , about 29% of the urban houses and 15% of all houses had access to safe drinking water at the time of

2464-573: The pre- trap rock topography was more elevated in Dogu'a Tembien as compared to more southerly areas. Three major formations may be distinguished: lower basalts , interbedded lacustrine deposits and upper basalts . Almost at the same time, the Mekelle Dolerite intruded the Mesozoic sediments following joints and faults . A new magma intrusion occurred in the Early Miocene , what gave rise to

2520-446: The river. All in all, average sediment yield is 3627 tonnes per km and per year. All measurements were done at purposively installed stations, in the years 2006-2007. Runoff mostly occurs in the form of high runoff discharge events that occur in a very short period (called flash floods ). These are related to the steep topography, often little vegetation cover and intense convective rainfall. The peaks of such flash floods have often

2576-422: The rock, forming two courtyards , both hewn but not open at the upper side. The first courtyard holds graves; between the two, there is a block of stone with a cross in the window opening in its centre. The three-aisled church has a depth of four bays. There are entrances on both sides through hewn corridors. The church ceiling has a consistent height, holding cupolas, arches and capitals in each bay. The hewn tabot

2632-428: The runoff coefficient was smaller (13% in 1935 against 23% in 2014). As a consequence, discharges in the river were less and the river was narrower than today. Up to the 1980s, there was strong pressure on the environment, and much vegetation disappeared. This river had its greatest discharges and width in that period. The magnitude of floods in this river has however been decreased in recent years due to interventions in

2688-579: The soils are saturated with water in many places. The percentage of total rainfall that directly leaves the catchment as storm runoff (also called runoff coefficient) is 23%. This is high, in comparison to other rivers of the Giba River basin, and has been explained by the fact that the larger part of the Tanqwa basin is composed of impervious rocks, particularly Ashangi Basalts , Alaji Basalts and Precambrian basement rocks. The total amount of sediment that

2744-481: The summer rainy season the dominant wind direction is from the southwest, whereas in the rest of the year winds blow from the east. The farmers have adapted their cropping systems to this spatio-temporal variability in rainfall. Given the good chilling conditions , it is possible to grow apple at elevations above 2400 metres, such as in Dingilet or Mashih . Climate models predict intensified summer rainfall in

2800-413: The summer rainy season, when the lands near the villages are occupied by crops. Young shepherds will take the village cattle down to the gorge and overnight in small caves. The gorges are particularly attractive as a transhumance destination zone, because there is water and good growth of semi-natural vegetation. Boulders and pebbles encountered in the river bed can originate from any location higher up in

2856-543: The top of a rock pinnacle that overlooks Addi Nefas village. This church has also been hewn in Adigrat Sandstone . The Lafa Gebri’al rock church ( 13°35.87′N 39°17.25′E  /  13.59783°N 39.28750°E  / 13.59783; 39.28750 ) is now disused. It was hewn in a tufa plug. The church boosts a semi-circular wooden arch of approx. 1.5 metre across (in one piece). Ruba Bich’i 's village church ( 13°36′N 39°18′E  /  13.600°N 39.300°E  / 13.600; 39.300 )

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2912-548: The upper side of the cliff, there is an alignment of cavities: the “windows” of a gallery parallel to cliff and river. The cave floor holds with clay pots that would have served as food containers for villagers who went there hiding during an early 20th C. conflict. The Tinsehe caves, a cave system opening into the Upper Tsaliet River gorge near Addi Idaga ( 13°42′N 39°12′E  /  13.700°N 39.200°E  / 13.700; 39.200 ). The entrance near

2968-425: The village of Mahba at a height of about 2500 metres, is some 64 m long ( 13°37′14″N 39°03′05″E  /  13.620592°N 39.051313°E  / 13.620592; 39.051313 ). It contains engravings and paintings of Pastoral Neolithic age. The history of the tabia is strongly confounded with the history of Tembien . Most inhabitants are Orthodox Christians . The following churches are located in

3024-784: The village of Mahba in Aregen at a height of about 2500 metres, is some 64 m long ( 13°37′14″N 39°03′05″E  /  13.620592°N 39.051313°E  / 13.620592; 39.051313 ). It contains engravings and paintings of Pastoral Neolithic age. The Danei Kawlos cave in the Tsech'i gorge at the west of Menachek at a height of about 2020 metres, is some 13.5 metres long ( 13°37′19″N 39°01′59″E  /  13.621862°N 39.033077°E  / 13.621862; 39.033077 ). It contains lithic tools, potsherds, and faunal remains of Pastoral Neolithic age. The May Hib’o cave ( 13°31′N 39°14′E  /  13.517°N 39.233°E  / 13.517; 39.233 ),

3080-517: Was from here that the offensives were organised till the conquest of Addis Ababa in 1991. In nearby Melfa , the Amhara EPDM party had its own headquarters in a cave. As Dogu'a Tembien holds a wide variety of rock types , there is expectedly a varied use of rock. Average annual precipitation (in Hagere Selam ) is 778 mm. Mean temperature is 13.3 °C, oscillating between average daily minimum of 10.9 °C and maximum of 22 °C. As it

3136-691: Was probably caused by a regional uplift. In the beginning of the Caenozoic , there was a relative tectonic quiescence, during which the Amba Aradam Sandstones were partially eroded what led to the formation of a new planation surface. In the Eocene , the Afar plume a broad regional uplift deformed the lithosphere , leading to the eruption of flood basalts . The magma followed pre-existing tectonic lineaments. A mere thickness of 400 metres of basalt indicates that

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