This elaborate towering structure was once famed for its revolutionary height.

The largest university building in the West is a gothic masterpiece containing dozens of theme rooms based on different countries.

Dr Barnes' $25 billion private collection of art and arboretum.

This palatial botanical garden is home to one of the largest pipe organs ever installed in a private residence, and a piece of Wood's cycad.

Frank Lloyd Wright’s most iconic home dangles over a Pennsylvania waterfall.

Philadelphia boasts one of the best — and most often overlooked — traditional Japanese gardens in North America.

America's most famous museum of medical oddities is home to the remains of Albert Einstein's brain.