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The Tarr Steps is a clapper bridge across the River Barle in the Exmoor National Park, Somerset, England. They are located in a national nature reserve about 2.5 miles (4 km) south east of Withypool and 4 miles (6 km) north west of Dulverton. A typical clapper bridge construction, the bridge's listing assesses it as medieval in origin. The stone slabs weigh up to two tons each. The bridge is 180 feet (55 m) long and has 17 spans. It has been designated by English Heritage as a grade I listed building and scheduled monument.