The reservation was built from land purchases begun in 1895. It took a decade to untangle the deeds and assemble all the lands at South Mountain. Before he delegated design of the Essex Parks to his stepson's firm, Frederick Law Olmsted visited the newly acquired reservation. He regarded it as some of the most beautiful and promising terrain he had ever seen anywhere. The design of South Mountain was finalized by the Olmsted Brothers in stages over the years. A good deal of construction work—trails, footbridges, shelters, etc.—was carried out by the Civilian Conservation Corps in the 1930s.