Tryon Creek State Natural Area, Nature reserve in Lake Oswego, United States.

Tryon Creek State Natural Area is a 645-acre (261 ha) park between Boones Ferry Road and Terwilliger Boulevard, mostly in southwest Portland with a northern section in Lake Oswego. Tryon Creek bisects it from north to south. The park has 8 miles (13 km) of hiking trails, a 3-mile (4.8 km) paved bicycle path along Terwilliger Boulevard, and horse trails including the 2-mile North Horse Loop and 3-mile West Horse Loop.

A doctor named Socrates Hotchkiss Tryon claimed the land in 1850 and logging operations took place here for over a century. Timber cutting stopped in 1961, after which conservation work began to restore the forest.

The park's name comes from Socrates Hotchkiss Tryon Sr., who filed a donation land claim at the south end of the canyon in 1850. Each spring the Trillium Festival celebrates the trilliums that carpet the forest floor. The Friends of Tryon Creek Park, formed in 1969, still organizes volunteers and events.

The visitor center provides trail maps and information to help you navigate the many paths through the property. Wear good shoes since the trails wind through wet, hilly forest terrain that can be slippery, especially after rain.

The 1962 Columbus Day Storm blew down many trees left after logging ended in 1961, and huge cedar stumps from the 1912 Boone's Ferry Wood and Tie Company operations still stand in the park. The old logging road became today's Old Iron Mountain Trail.