The Washington DC Half Marathon Calendar is a complete simplistic listing of Washington DC half marathons.  Currently the Washington DC half marathon schedule has 2026 Washington DC half marathons and 2027 Washington DC half marathons as they roll in. Washington DC half marathons 2026 & Washington DC half marathons 2027 also identify trail half marathons and walker friendly half marathons by a (T) symbol and a (W) symbol.  The (T) means it is a TRUE trail half marathon 21k (off road, switchbacks, etc) and a (W) means it is truly "official walker friendly" requiring the half marathon to allow a minimum of 18:32 mile pace, minimum 4 hours for participants to finish the 13.1 mile distance.