Camp 4 is a campground in Yosemite National Park. It became notable after World War II as the hangout for rock climbers with many spending months there (not necessarily legally). It is located near Yosemite Falls, on the north side of the valley. There is a single parking lot at the campground, and no driveways connecting to individual campsites, so visitors must carry their gear in. Nearby boulders have long been used for bouldering. Among the boulders located here, the Columbia Boulder is probably the most famous. On it is the world-renowned boulder problem called the Midnight Lightning, first done by Ron Kauk in 1978. It is easily recognizable by a painting of a white thunderbolt next to it.