Perched on the edge of the water-filled west side of the Nation­al Mall, the open-air pan­theon, ded­i­cat­ed to America’s third pres­i­dent, is one of the most serene spots in the city. The neo­clas­si­cal style memo­r­i­al was only com­plet­ed in 1947. It looks its most beau­ti­ful framed by the cher­ry blos­soms in spring.