The cliffs and valleys all around the Ani plateau are riddled with hundreds of caves that guides have collectively dubbed Ani's 'Underground City'. Mostly carved out by humans over the millennia, the caves have served as dwellings, animal shelters, chapels and – the smallest ones – pigeon houses to provide a source of eggs and fertiliser. Visible clusters lie in the gully below the Church of Grigor Pahlavuny and across the valley from the Seljuk Palace.
Anybody can have a poke around the western caves but don't wander down to the Arpaçay Gorge, which is off limits due to border sensitivities. To find the most fascinating caves – multichambered caravanserais, churches with angel frescoes, domed pigeon houses and long tunnels inside the rock – you'll generally need a guide. Celil Ersözoğlu is recommended and his underground city explorations will add a couple of extra hours to your time in Ani.