Marlborough-Blenheim Hotel, Atlantic City, New Jersey.
It wasn’t the first reinforced concrete building in the world, but it was the largest. Construction started on the Marlborough-Blenheim in 1905, an era when Atlantic City’s boardwalk was bursting with tourists clamoring for curiosities like the Diving Horse and Dr. Couney’s Premature Infant Exhibit. With the end of World War II came family car trips, jet travel, suburbia, and, on the boardwalk, crime, poverty and corruption as tourism declined. The Marlborough-Blenheim was demolished in 1979. Today the site is occupied by a Bally’s Casino with a facade built to echo the days of Dimah the Diving Horse.