Now in its 26th year, the Rolling Thunder motorcycle rally rumbled through Arlington and D.C. yesterday in an annual tribute to fallen U.S. troops and the soldiers who went missing in action and never returned home. By some estimates, The Washington Times reports, Sunday’s ride brought in 500,000 bikers revving their engines from the Pentagon, past Arlington National Cemetery, and around the National Mall.

Although a bit cooler than normal, yesterday provide picturesque conditions for the rally, as bikers from across the United States rode under a clear azure sky. Rolling Thunder, which advocates for the U.S. government to provide accountable records of its troops declared prisoners of war or missing in action, has held its annual ride every Memorial Day since 1988.

The 10-mile ride began with a rally at the Pentagon, up to Arlington Memorial Bridge, and across the Potomac to Constitution Avenue where the bikers circumnavigated the National Mall, with numerous spectators lining the route.