The Conch Bar Caves are the largest above-ground cave system in the Caribbean, extending for several kilometres through the limestone spine of Middle Caicos. The caves are not commercial tourist infrastructure — there is no lighting, no paved paths, no gift shop. You explore them with a local guide using headlamps, crawling through some passages and walking upright in others, past formations of stalactites and stalagmites built over millions of years.
The caves are home to a large colony of bats and to occasional pygmy boas. Several chambers open to skylights where trees grow down from the surface. The experience is genuinely wild and genuinely impressive, and the lack of crowds or facilities is part of the point. Guides can be arranged through guesthouses in Conch Bar village or Bambarra.