Wuppertal, Germany

Wuppertal sits along the Wupper river in North Rhine-Westphalia with roughly 360,000 residents and was founded in 1929 by merging the towns of Barmen, Elberfeld, and several neighboring communities. Its signature transit line, the 1901 Wuppertal Suspension Railway, glides 13.3 kilometers above the river and streets and carries about 85,000 daily passengers. The Engels House museum, dating to 1786, marks the birthplace of Friedrich Engels, who co-authored The Communist Manifesto with Karl Marx in 1848. The Von der Heydt Museum, opened in 1850, holds paintings by Picasso, Monet, and Caspar David Friedrich, while the 1890 Botanischer Garten cultivates 4,000 plant species across 3.5 hectares.