Portable toilets will be located at each fluid and each first aid station for all races. For the Boston Marathon, stations are every mile beginning at mile two. For the B.A.A. Half Marathon, stations are every other mile beginning at mile two. We've also added many port-a-johns to the start area and finish area of each race. Course Information Boston Marathon B.A.A. 10K B.A.A. Half Marathon Are portable toilets available along the Boston Marathon, B.A.A. 10K, B.A.A. Half Marathon courses?