Skyline-defining towers have proliferated across the Midtown and Lower Manhattan skylines since the start of the 2010s, with the new World Trade Center joined by clusters in Hudson Yards, and 57th Street. Now, as One Vanderbilt approaches the 1,000-foot mark, a new race is appearing on the horizon in Midtown East. First, JPMorgan announced plans for a 1,400-foot-plus behemoth at 270 Park Avenue. Today, renderings have been released for Harry Macklowe’s planned office tower at 5 East 51st Street, which the developer has dubbed “Tower Fifth”. The supertall would become the tallest building in New York City by roof height upon completion, soaring 1,556 feet and six inches above the streets down below.