A collection of historic buildings in central Birmingham blend seamlessly into the cityscape but have an interesting story to tell.

A dedication plaque on this Boston tunnel is a microcosm of a massive, controversy-laden construction project.

These abundant, over-the-top monuments are so widely scattered that they define the entire compact capital cityscape, often leading to jokes about whether there are more statues than residents.

In this German city center, the streets have no names.

The largest underground pedestrian tunnel system in the U.S. mostly caters to the people working in the offices above, but provides a great, air-conditioned way to traverse the city.

This tiny, triangular block has held the world record since 1964.

In the summer of 1957, a massive architectural exhibition showed off the future of urban living in this German neighborhood.

This pair of unsuspecting buildings are in fact the very first modern skyscrapers in Europe.

This skyscraper once housed weapons during the revolution and was the scene of two brutal crimes that shocked São Paulo society.

This scenic cable car ride glides 100 feet above Mexico City.

A settlement that was stopped in the middle of construction, leaving behind paved roads, curbs, light poles, a stormwater drainage system, and even a basketball court, but no houses.

Built to celebrate the glory of a new queen, this forgotten monument has moved around Madrid three times, reflecting 200 years of political whims and city redevelopment.

This museum offers a glimpse into early 20th-century Glasgow life.

A city park that sits on top of a freeway.

An entire subdivision was accidentally built on a flood plain, resulting in its eventual demolition—but the streets are still there.

The oldest alley in San Francisco is paved with a reminder of the city's original shoreline.