This concept image shows an aerial view of the proposed Zootopia in Denmark. The designer says the idea is to let the animals roam free, separated from visitors by hidden barriers.
Bjarke Ingels Group
The Shard, the tallest building in Western Europe at 1,016 feet, was inaugurated in London in 2012. It got its formal name when the builders adopted the term used by critics, who called it a "shard of glass" in the city's skyline.
Sky City, a replica of Paris, is a 40-minute drive from Hangzhou in East China's Zhejiang province. The rich people that developers hoped would move here never materialized.
One World Trade Center stands at its full height of 1,776 feet Friday, after a crane lifted its spire into place. The New York City skyline is seen here from the Heights neighborhood of Jersey City, N.J.