It was originally a Native American trail, running roughly along what is now the eastern edge of Prospect Park and taking advantage of a low point in the Heights of Guan that form the spine of Long Island. A monument beside the former Flatbush Road, now inside the park, commemorates an attempt to block the road at Battle Pass during the Battle of Long Island. For much of the 19th century, it had a plank road run by a turnpike company. Historic homes line the neighborhoods around the avenue, which in the late 1920s was straightened to its current form. Streets such as Amersfort Place that are remnants of old parts of the avenue remain in the city grid as an echo of the past.