Search for April half marathons! Search for your next April half marathon at the April Half Marathon Calendar USA website page. The half marathon running event calendar currently has April half marathons 2027 and April half marathons 2028 as they roll in. All 2027 April half marathons should be posted by now. For races that are late in posting their April half marathons, we do our best to get those dates updated throughout the year, as race directors and race organizers updat