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Thursday, July 23, 2015

Agate Bridge - Petrified Forest National Park


Our May 2015 visit to Petrified Forest National Park continued with a quick stop at Agate Bridge. The parking area for the bridge is located 17.5 miles from the north entrance station and 9.9 miles from the south entrance station on the east side of Park Road. The interpretive sign onsite provides the geological background to the spectacle of a 110 foot long stone tree spanning a small gully:
Water created Agate Bridge and will destroy it. The fossilized tree that now forms Agate Bridge grew in a lush subtropical forest 217 million years ago. When this tree died, it washed into a river and its quick burial by river sediments prevented decay. Volcanic ash dissolved in the groundwater provided silica, which reacted with the log and slowly crystallized it into quartz. Millions of years later, rivers and streams eroded massive layers of rock strata to expose this fossilized tree. Inevitably, water now carving the small gully under Agate Bridge will cause its collapse. The supportive concrete span, constructed in 1917, is a tenuous attempt at preservation. Water will always have its way.
The small parking area provides places for 14 private passenger vehicles and one wheelchair accessible parking place. Parking for large RVs or trailers is not available as the turning radius is fairly small. The bridge is visible from the sidewalk at the contact station. A 125 foot path leads from the contact station to the bridge. Do not attempt to walk across the petrified log.

The historic Contact Station is being renovated

Agate Bridge viewed from the contact station

An idea of the size of the tree that fell so long ago

Looking down the length of the tree

The water channel upstream of the bridge

Agate Bridge from near the water channel

An entry fee of $10 per private vehicle is good for seven consecutive days. Other fee payment options include the America the Beautiful - National Parks and Federal Recreational Lands passes including the Annual Pass ($80), Senior Pass ($10 for lifetime), Access Pass (free with documented disability) and Military Annual Pass (free for active duty personnel).

The park website is http://www.nps.gov/pefo/index.htm.

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