Tonto Natural Bridge

Tonto Natural Bridge is believed to be the largest travertine natural bridge in the world and is one of Arizona’s most striking geological formations. The bridge stands 183’ high over a 400’ long tunnel that measures 150’ at its widest point. The natural bridge was formed over thousands of years as Pine Creek eroded the travertine deposits that had formed a travertine dam.

Tonto Natural Bridge is steeped in history stretching back to Hohokam and Tonto Apache settlements. The Tonto Basin specifically owes much continued habitation to a climate amenable to agriculture. The bridge itself was farmed seasonally, naturally topped with 5 acres of fertile soil.

After years of working in collaboration with The Nature Conservancy, the site was acquired by the State of Arizona and designated as State Park in 1969. Over the next 30 years funding was provided for trail development, roadways and picnic amenities as the park grew in popularity with Arizona’s residents. It is situated in the vast Tonto National Forest 90 miles northeast of Phoenix.

The original wooden pedestrian bridge and viewing deck on the Gowan hiking trail was built in the mid 1990’s but was closed by Arizona State Parks in 2019 due to concerns about structural integrity from decay and erosion from seasonal flooding. Its wooden guardrails, slippery walkways, and stairs were deteriorating and rotting out, posing an increasing risk to visitors with each passing season. Serving as the only accessible means to cross Pine Creek and get to the mouth of Tonto Natural Bridge, the entire structure needed a strategic repositioning.