The Sierra Nevada mountains in California are the source of a number of major rivers and their tributaries. The two largest of these rivers, the Sacramento and San Joaquin, play an important role in the state's history and economy as well as being a recreation destination for locals and tourists alike.
The source of the Sacramento is in Northern California, where the meeting of the South Fork and Middle Fork form the river proper. North of the town of Redding, the river officially starts near Lake Siskiyou. The source of the San Joaquin is in Central California, where its three forks merge together near Balloon Dome, a monolith in the Ansel Adams Wilderness.
The Sacramento meanders in a generally southern direction for 447 miles before it reaches the Sacramento-San Joaquin Delta. The San Joaquin River travels for 330 miles, first west and then northwest before it meets it pours into the Sacramento River near the town of Antioch. These two rivers form the delta, pass through Suisun, San Pablo and San Francisco Bay before finally reaching the ocean at the Golden Gate Bridge.
The delta that has been formed by these two rivers creates one of the largest estuaries in the United States. The Sacramento every October sees the return of massive numbers of king salmon from the Pacific Ocean that travel to spawning grounds. By contrast, the San Joaquin, due largely to irrigation for agriculture, is dry at certain times of the year and king salmon populations are limited. There is a river restoration project below the Friant Dam aimed at solving these problems.
The Sacramento historically was followed by American Indians as a trading trail, then by trappers in the early 1800s, by miners during the California gold rush and later became Interstate 5, the main north-south thoroughfare of the state. The San Joaquin was primarily used in the gold rush to ferry workers as much as 200 miles upriver in their search for gold.
Both rivers are known areas of recreation. The Sacramento, in particular, offers activities in three main areas that run along the entire length of the river. Activities include kayaking, swimming, tubing, fishing, birding and many miles of camping sites and trails. By contrast, the San Joaquin's activities are largely relegated to those above Friant Dam, which forms Millerton Lake State Recreation Area.