St. Patrick's Day parade, Rock `N' Roll Marathon to cause street closures and delays

(AP) -- A marathon will cause street closures in Washington this weekend, but Metro's rail stations will open earlier than normal to accommodate runners and spectators.

The Rock `N' Roll Marathon is being held Saturday and starts at 7:30 a.m. near the Smithsonian's National Museum of American History. The Metropolitan Police Department says street closures will begin as early as 12 a.m. and streets are expected to be reopened by 3 p.m.

Metro rail stations will open at 5 a.m., two hours earlier than normal.

The marathon course goes down parts of Constitution Avenue, crosses the Arlington Memorial Bridge, and winds through northwest and northeast Washington before ending near RFK Stadium.

On Sunday, several raod closures and detours will be in place for the District's St. Patrick's Day Parade.

The Associated Press contributed to this report.