Bartlesville, Oklahoma | Frank Lloyd Wright’s only realised skyscraper is just 19 storeys, but even 70 years after it was built, Price Tower sits higher than most buildings in this city, and the view from the top still stretches to the horizon where the rolling prairie starts to take shape.

The tower is a landmark in Bartlesville, and a rarity in the architect’s portfolio. Designed by Wright to resemble a tree, with green, oxidised copper panelling, it’s featured on a mural nearby that depicts bison, an oil well and other anchors of the city’s heritage.