Martinez grew as a port and small industrial center after gold was discovered in the Sierra Nevada in 1849. It is the seat of Contra Costa County. Martinez has a substantial stock of 19th and turn of the century houses and a fairly well preserved commercial district. In 1915 the Shell oil company began building a refinery on the eastern edge of the city. Today the refinery sprawls over many dozens of acres. It's storage tanks and stacks are visible from pretty much anywhere in town. There is a marina and park between the waterfront and downtown. Next to park is the pier where oil tankers from Alaska deliver oil to the refineries.
Just west of Martinez is the eastern end of the Carquinez scenic drive. This paved but unmaintained road is open to pedestrian and bicycle traffic only. It runs along the hills above the strait to Port Costa. The I 680 toll bridge from Martinez to Benicia has bicycle/pedestrian lanes on the Southwestern span. Interesting places nearby include: Waterbird regional park, Mare Island, Crockett and the Suisun Bay Reserve Fleet.