The Tour Carpe Diem is a 162-metre (531 ft) tall skyscraper in the La Défense business district, near Paris in France. Completed in 2013.
In days of yore, promoters were selling square meters in the highest possible skyscraper. Nowadays, there is much buzz around sustainable skyscrapers. Sustainable design calls for holes in the building, dented facades and dodgy angles. High-rise buildings boast green energy efficiency, some even claim sustainable vertical density.