The Wonderland Trail is a loop of 93 miles (150 km) around Mount Rainier, with about 27,000 feet (8,230 m) of climbing and the same amount of descent, through lowland forest, river valleys and high alpine ground. You cross a river valley, climb out, and do it again: the park's own description is "strenuous", and no day is flat.
The park publishes camps and the distance and climb between each pair of them, not a fixed itinerary. This page uses a 10-day clockwise loop from Longmire with 9 nights, because the park's mileages run clockwise from Longmire and 10 days keeps every day under 12 miles (19 km). Every distance and climb is the sum of the park's own segments between camps, not a measurement, so the 10 legs add up to 94.1 miles (151.4 km) and 27,154 feet (8,277 m) of climbing, a little more than the park's headline 93 miles (150 km) and 27,000 feet (8,230 m). It skips the Spray Park alternate between Mowich Lake and the Carbon River, which day 5 describes.
The decision that matters is the permit, and it comes months before the hike: the early-access lottery opens in February, and the full circuit is hard to assemble after it. Current note (checked 1 November 2026): the park's alerts page says the Wonderland Trail is closed by fire from the Carbon River Suspension Bridge to Frozen Lake near Sunrise, with the camps in between, while its trail conditions page says the trail is closed from the Carbon River to Summerland. The SR165 Fairfax Bridge outside the park is closed too, so there is no road to Carbon River or Mowich Lake and no food caching at Mowich Lake. The trail conditions page also says no full Wonderland Trail circuit permits will be issued until further notice. Read both pages before you apply, and again before you leave.