WASHINGTON — Road-weary motorists in the D.C. area may think they’ve seen it all — but this may be a first.

A posse of cowboys including a mule wagon rode into D.C. Thursday morning, causing some rush hour traffic delays in Manassas, Virginia, along the Route 234 and Route 29 corridors as well as in parts of downtown D.C.

The so-called “Grass March Cowboy Express” made its way to the U.S. Capitol to protest what it sees as federal meddling with wild horses’ water and grazing rights.

The coast-to-coast “Cowboy Express” relay ride started in California in late September.

Walked through Georgetown by the Grass March Cowboy Express. They've been riding since San Fran — 2800 miles total. pic.twitter.com/p33hiVABzH

— Angela Haupt (@angelahaupt) October 16, 2014

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Post by Grass March – Cowboy Express.

Post by Grass March – Cowboy Express.

Below is a map with their route information:

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