Tunnel Log is a tunnel cut through a fallen giant sequoia tree in Sequoia National Park. The tree, which measured 275 feet (84 m) tall and 21 feet (6.4 m) in diameter, fell across a park road in 1937 due to natural causes. The following year, a crew cut an 8-foot (2.4 m) tall, 17-foot (5.2 m) wide tunnel through the trunk, making the road passable again.