When a city's topography is as complex as that of southwest China's Chongqing, getting around presents a unique set of challenges. Copious undulating hills make biking out of the question, staircases weave throughout the metropolis and infrastructure must maneuver around slopes, valleys and waterways — they don't call Chongqing a "3-D City" for nothing! But the city has leaned into these transportation challenges, accommodating the landscape at every turn and dreaming up some pretty innovative solutions. In the municipality, city structures are very much embedded into the landscape: the mountains and the metropolis are one.

What's a civil engineer to do when a residential building needs to rise in the path of a planned sky train line? Tunnel the sky train straight through the building, of course! Liziba station on Line 2 of Chongqing's sky train system is located in the sixth through the eighth floors of a 19-story residential structure. The train disappears into the building as it passes through, like something out of a futuristic science fiction film. 

You would think the residents would be subjected to endlessly bothersome noise all day long, but the station was constructed with noise reduction equipment that insulates the clamor. What the building's occupants end up hearing isn't much louder than a dishwasher, and it's hard to beat the convenience of having mass transit stop in your very own building. 

Staircases snaking throughout Chongqing provide routes by which to navigate the city's countless slopes. But hiking up endless stairs can be tough on the knees — not to mention exhausting, especially during one of the city's notoriously scorching summer days. With the Huangguan Escalator, a piece of machinery does the work for you. 

This 112-meter long escalator is one of the longest in Asia. Considered part of the public transit system, it requires a fee to ride and takes two-and-a-half minutes to complete a one-way trip. Beware of vertigo — this escalator moves faster than those you're probably accustomed to! 

In 1987, the Yangtze River Cableway began operation as a cheap alternative to expensive new bridges. It offered riders an affordable and efficient way to travel between the Yuzhong and Nan'an districts located on opposite sides of the Yangtze River. As the city developed, more methods of cross-river transport appeared, and today, multiple bridges and sky trains provide routes that traverse the river. But the cableway continues running, offering riders stunning views of the river flanked by glossy skyscrapers and rolling hills.