Martinez sits on the southern shore of the Carquinez Strait, where the waters of the Sacramento–San Joaquin Delta meet the northeastern reach of San Francisco Bay. As the county seat of Contra Costa County, it combines the responsibilities of a small government center with the character of a historic East Bay waterfront town. Its population is roughly 37,000. The city's story begins in the California Gold Rush era, when Martinez served as a ferry crossing and later incorporated in 1876, making it one of the older cities in the county. The downtown grew around the ferry landing and the rail and maritime activity of the strait, and the city has long been a transportation waypoint between the Central Valley, the Delta, and the Bay Area. Martinez's best-known resident is naturalist and Sierra Club founder John Muir, who made his home here from 1890 until his death in 1914. The Victorian mansion where he lived is preserved as the John Muir National Historic Site, and the nearby Mount Wanda open space is part of the same National Park Service site. That legacy gives the city an identity rooted in conservation and the outdoors. Today Martinez balances its historic downtown with working residential neighborhoods that climb the hills above the strait. Amtrak's Capitol Corridor line stops downtown, BART is a short drive away in the county, and major freeways place both Oakland and the Central Valley within reach. For residents, the appeal is a walkable, character-rich town with genuine waterfront access and a strong sense of place in the East Bay.