Santa Cruz is where most people fly to on the Galapagos islands. With a population of over 15.000 Puerto Ayora, the main town on Santa Cruz, it is by far the largest place on the islands and has a good infrastructure. As a side note, it also has the best bikes for rent that I have found so far in Ecuador!
Although most people leave for a cruise from here, there is quite a few things to do on the island itself. I enjoyed the 1.5 hour walk to tortuga bay and back, with its candelabra and opuntia cacti, iguanas, and various birds to watch. The short walk to Playa de las Alemanes and Las Grietas was equally enjoyable, and especially the swim in the refreshing brackish water of Las Grietas was great fun.
I rented a bike to cycle over the hills to the El Chato tortoise reserve and the twin craters of Los Gemelos. The bike ride was fairly strenuous, but as the gears were shifting perfectly I managed it without problems, and the downhill ride in the evening was just great. See pictures for both places, they say more than words!
Another day I went
for a hike to Luna Media (a half moon shaped hill), Cerro Crocker (with 864m the highest elevation ) and the strangely platform shaped hill Puntudo. It was an enjoyable 4.5 hours hike, but I would never have known where Puntudo is and how to get there from Cerro Crocker, if I hadn’t met by chance two guys on horses on Cerro Crocker. There is scalesia, miconia, fern and quinine vegetation along the hike. From the top of Cerro Crocker there is an amazing view over the entire island.