The most easterly island in the Galápagos , San Cristóbal is the administrative center of the province, and its port, Puerto Baquerizo Moreno, is the capital. It’s not as busy as Santa Cruz  and retains the feel of a more modest tourism hub.
The island has a troubled history, though, having been the site of a large penal colony in the late 19th century inland at the small town of El Progreso. These days, it is a pleasant enough place with some fantastic visitor sites, and it makes a slightly cheaper, quieter alternative base to Puerto Ayora, although excursion options are more limited.
San Cristóbal is also leading the way in the archipelago’s renewable energy drive, with 60 percent of its energy coming from wind and solar power. The hope is to eliminate diesel completely from the island in the next five years.
Near Baquerizo Moreno are several short walks to interesting sites. Northeast of the center is The Interpretation Center, which has arguably the best exhibition in the archipelago on the islands’ history and ecology. Beyond this are walks to Las Tijeretas, renowned for frigate birds, and Playa Cabo de Horno, a good spot for snorkeling.
On the opposite side of town you can walk among a large sea lion colony at La Lobería. Farther afield, the most popular boat trips are to Isla Lobos, excellent for snorkeling with sea lions, and Kicker Rock, also known as León Dormido, one of the best snorkeling and dive sites in the entire archipelago, with large populations of sharks as well as rays and turtles.
At the northeastern end of the island, Punta Pitt has large colonies of red-footed, blue-footed, and masked boobies. In the highlands, an interesting day trip takes in the freshwater Laguna El Junco, the beach of Puerto Chino, and the large giant tortoise reserve of La Galapaguera.
San Cristóbal has some excellent sites, and most are reachable on day trips from Baquerizo Moreno. They are usually quieter than many of the sites from Puerto Ayora because fewer visitors base themselves on San Cristóbal. Playa del Amor and La Lobería can all be visited independently, but the best marine sites require a boat trip.
Isla Lobos is a tiny rocky island 30 minutes north of Baquerizo Moreno by boat. Walking on the island is prohibited, so just jump straight in for excellent snorkeling with sea lions. This site is commonly combined with one of the Galápagos ’s most famous landmarks, Kicker Rock, also known as León Dormido (Sleeping Lion).
Some people think it looks like a foot; others see the shape of a lion. Whichever name you prefer, this is one of the best snorkeling and dive sites in the archipelago. The sheer-walled volcanic tuff cone has been eroded in half with a narrow channel in between.
This is a prime spot to see sharks—white-tipped reef sharks are commonly seen in and around the channel, while divers can go deeper to see awesome schools of hammerheads. Sea turtles and a wide range of rays are also common.
Boats are not allowed in the channel, so wait at either end while you snorkel or dive. Day trips often stop at the long white beach of Cerro Brujo afterward for more relaxing swimming, snorkeling, and sunbathing.