The Navy Air Force Half Marathon in DC can sometimes get lost in the shuffle of armed forces themed races in the District, held the month before its more successful sibling races of the Army 10 miler and the obnoxious older brother that is the Marine Corps Marathon. The upside to all of this is that the crowds are smaller, the course open, and with all the scenery you'd hope to get from a DC race: the National Mall, the Potomac, and Rock Creek Parkway. The price tag is high, especially for late registrants, but as one of the few half marathons in the District and without the omnipresent crowding that you get at other headline DC races, it's worth the extra money.