If you google Galápagos Islands you will almost certainly see this picture:
You will likely see even better photos than the one above as we were there at the wrong time of day for optimal photo lighting.
The hike was mostly just climbing the 366 old wooden stairs and many boardwalks to the top of the volcano where there is a great viewing and picture taking spot. Along the way we stopped to learn a bit about volcanology, spatter cones, calderas, and craters.
The naturalists on board are all great and really knowledgeable. Most, if not all, of them were born on the islands and you can tell they all really love it.