Red Rock Island

Red Rock Island (variously known as Moleta, Molate Rock, and Golden Rock ) is an uninhabited, 5.8 acre island in the San Francisco Bay located just south of the Richmond–San Rafael Bridge. The property is the only privately owned island in San Francisco Bay. The boundaries of three counties – San Francisco, Marin, and Contra Costa – converge on the island. The Contra Costa portion (most of the island) is incorporated inside the city limits of Richmond.

The mountain of bright red earth and rock is 500 ft across from east to west, 750 ft from north to south, and rises out of the bay to a height of 151 ft. It is surrounded by some of the deepest water in the North Bay, nearly 60 ft deep.

History
Selim E. Woodworth was the first owner and resident of Red Rock Island, where in the 19th century he built a cabin and maintained a hunting preserve. The island appears, labeled "Molate Island", on an 1850 survey map of the San Francisco Bay area made by Cadwalader Ringgold and an 1854 map of the area by Henry Lange.

The island was once mined for manganese. It was privately purchased in the 1920s. After a series of owners, David Glickman, at the time a San Francisco attorney and part-time real estate buyer, purchased the island in 1964 for US$49,500.

In the 1980s, a plan was proposed (but never implemented) to remove the top half of the island (which would be sold for highway roadbed construction). The island would then be developed with a 10-story hotel and casino, and a yacht harbor on the lee (north) side. Water and power would be provided from lines connected to the San Rafael Bridge.

In the 21st century, the island was placed on the market multiple times:
 * in 2001, offer to buy the island was made to the California Department of Fish and Game;
 * in June 2007, Glickman, at the time a gem dealer in Thailand, announced that Red Rock Island was for sale for US$10 million;
 * in early 2012, the island was listed with a realtor at a price of US$5 million;
 * in late 2023 Brock Durning, who inherited the island from his father, Mack Durning, placed the island on the market for US$25 million, first time this property was offered through a multiple listing service.

No conservation groups or agencies have so far expressed interest in buying the island, though some have considered it.

The island is mentioned and described as "Blue Island" in the novel The Circle by Dave Eggers.