Concepción is the perfect-coned northern volcano of Ometepe, rising 1,610 metres straight out of the lake. From the western shore of Granada or Rivas it is the dominant feature of the southern horizon — a textbook stratovolcano shape that draws comparisons with Mount Fuji.
The climb to the summit is brutal — ten or eleven hours round trip, with no water, no shade and loose volcanic rubble for the final third. Guides are mandatory and worth the money: they will turn you back if cloud comes in, which it almost always does. For most travellers the better option is the lower-slope hikes from Moyogalpa or Altagracia, which give you the views without the suffering. The volcano can puff ash without warning, so check current activity before any climb.