It bears the name of the Patron Saint of seafarers, "St. Christopher". Its English name was given after William Pitt, 1st Earl of Chatham. It has an area of 558 square kilometres (215 sq mi) and its highest point rises to 730 metres (2395 ft). This islands hosts frigate birds, sea lions, giant tortoises, blue and red footed boobies, tropicbirds, marine iguanas, dolphins, swallow-tailed gulls. Its vegetation includes Calandrinia galapagos, Lecocarpus darwinii, and trees such as Lignum vitae.The largest fresh water lake in the archipelago, Laguna El Junco, is located in the highlands of San Cristóbal. The capital of the province of Galápagos, Puerto Baquerizo Moreno, lies at the southern tip of the island.