From Interstate 80 or 580, exit at University Avenue and proceed west.
Berkeley Pier is California's longest pier, even in its deteriorated state. However, when piers are generally measure, they distinction comes between bay piers and over-the-ocean piers in the Pacific. The ocean piers tend to provide a markedly different experience--stronger waves, and unfettered sunsets. That's why the Berkeley Pier isn't commonly categorized as one of California's pleasure piers, that it does offer strolls, free fishing opportunities and most the same activities as other piers.
When built in 1926-27, the pier was a hearty 3.5 mile concrete extension into the San Francisco Bay designed to connect Berkeley with San Francisco as a roadway and ferry system. By the late 1930s the ferry wasn't needed as the Bay Bridge became operational and of course, was the convenient, quick option for shopping, entertainment, and doing what Californian's do best--commute to and from work.
Berkeley Pier today is down to around 3,000 feet of usable space open to the public. At well over half a mile long (5,280 feet in a mile)