Santa Cruz, Galapagos, Ecuador

Los Gemelos (the twin craters) Long ago when Santa Cruz island was an active volcano, lava flowed freely from the highlands summit down to the coast. Lava tunnels (or tubes) and magma chambers form when the top level of lava is slow moving and solidifies, while the lava below continues to flow. The result is a hollow chamber or tube, covered over by a thin layer of solidified lava. In the case of Los Gemelos, the fragile lava surface caved in due to erosion or tectonic shifts. When the chamber roof collapsed it revealed these huge sink holes. An impressive eight of the thirteen Darwin Finch species can be spotted here. The differences between finches is quite subtle; look for differences in color, beak size, body size and behavior to correctly identify them. We mostly did not go to that level.

Bellavista Lava Tunnel. This is the largest lava tube I have ever been in. As you descend into the tunnels via stairs, you quickly lose sight of the sun and enter the darkness. Even though they have lights hung throughout. you still have limited visibility. My spouse spotted two barn owls in the gloom, but mostly it is just a very cool place to hike through.