(Uploaded by Plazi for the Bat Literature Project) Despite the high geoheritage value of caves and karsts, northern Ethiopia's largest cave at Zeyi (13.5586°N, 39.1454°E) in the Dogu'a Tembien district has received little attention so far. We have studied its geological, geomorphic, socio-cultural and historical dimensions in a holistic way. The basal member of the Antalo Limestone, in which the Zeyi cave is located, consists of grainstone and wackestone with subordinate marly interlayers. Over a length of 364 m, the oval-shaped gallery displays stalagmites, stalactites, five columns, dissolution holes ("bell-holes") following joints, stalagmitic floors and other concretions or speleothems. In the absence of any dating of the cave, we contrasted its elevation above the current local base level with known average incision rates of the northern Ethiopian highlands to reconstruct its age, which was calculated as at least 2 to 4 million years. The palaeo-environmental information that is archived in the Zeyi cave sediment would hence cover the Pleistocene. The graves in the sediment at the bottom of the Zeyi cave further indicate that the place could be an ancient burial site, which gives scope for archaeological research. Zeyi boosts a unique combination of abiotic, biotic and cultural components: the nineteenth c. church under the overhanging cliff; the unique cave; the speleothems, cliffs and gorges; and the cave's bat colony which has been genetically confirmed to be composed of three syntopically roosting species. Accounting for a good balance between cave research, community-based geotourism, geoconservation and biodiversity conservation, the Zeyi cave has strong credentials to become a top geotouristic site in northern Ethiopia. However, major work needs to be done, including granting access for women and organising community-based geotourism.