Yosemite is where the idea of a national park started. In 1864 Abraham Lincoln signed the Yosemite Grant, which handed the valley and the Mariposa Grove of giant sequoias to California to protect, and in 1890 John Muir's campaign turned the wider area into a national park. Glaciers did the sculpting: the Valley is a granite trough about 7.5 miles long and 3,000 to 3,500 feet deep, with waterfalls dropping off the rim and a river running quietly along the floor.
It is also a park with a clear schedule, and ignoring that schedule is the way most trips go wrong. Yosemite Falls is a thunder in May and June and a dry streak by late summer. The Tioga Road to the high country closes for the winter, the Glacier Point road closes with it, and the Mariposa Grove shuttle stops in late November. Five days is the right length: two days in the Valley, one on the rim at Glacier Point, one among the sequoias, and one on the Tioga Road. Everything here has a fallback for the day a road is closed or a waterfall has gone dry.
The plan starts in the Valley, where the famous views are, and spreads outward day by day. We recommend starting on a Monday. The park's own advice is to visit on weekdays, when parking and traffic are easier, and this order puts the two longest drives, Glacier Point and the Tioga Road, on Wednesday and Friday. If you fly into San Francisco first, see 5 Days in San Francisco and drive over on day one. More about the country on the United States page.