The Rock-Hewn Churches of Tigrai, Northern Ethiopia: A Geological Perspective

Ethiopia is endowed with many rock-hewn churches, with the largest group in central and eastern Tigrai. These churches can be divided into four zones: the Atsbi, Hawzen-Ger'alta, Sinkata-Adigrat, and Tembien, with more than 100 rock-hewn churches of different ages, sizes, and histories. However, they have one thing in common: All are carved into sandstone. The Enticho, Adigrat, and Ambaradam sandstones (Permo-Carboniferous, Triassic - Middle Jurassic, and Early Cretaceous, respectively) are extensively exposed in these areas and are characterized by thick and massive beds of coarse- to fine-grained and well-sorted successions. These sandstones are easily carved, yet compact enough to withstand pressure. Although limestone, basalt, and crystalline rocks are exposed in the same area, few rock-hewn churches have been carved into them. The rock type is, therefore, the most important factor in the location of these rock-hewn churches.