Much of the time when I travel, it is to experience a new culture, try new foods, or enjoy a natural wonder. But there are man-made wonders out there as well. As someone with an engineering education, I remain highly interested in seeing some of the most amazing structures and other engineering accomplishments around the world. Here are the top ten on my list:

Millau Viaduct, France

The tallest bridge in Europe is one of the most impressive structures I’ve ever seen. Seen in a photograph, that is. I have yet to visit it. At its highest point, the bridge deck stands over 1,000 feet above the Tarn River far below!

With congestion plaguing nearby Millau during summer travel season, the bridge allows the town to be bypassed by people traveling between Paris and the south of France. The Millau Viaduct has not only been an excellent solution, it is one of the most outstanding engineering achievements of all time.

Burj Khalifa

If the tallest bridge in Europe isn’t enough for you, the tallest building in the world should be. Completed in 2010, the Burj Khalifa didn’t just snatch the record from Taipei 101, is absolutely annihilated it. Standing over half a mile tall, the Burj Khalifa is the first of what . It was over 1,000 feet taller than the next tallest building when it initially opened, which is absolutely insane.

I have little interest in visiting Dubai other than to visit this megatall skyscraper. Even years later, there are only a handful of other building that are either completed or under construction that exceed 600 meters. If the Jeddah Tower is completed, a 1,000-meter structure under construction in Saudi Arabia, the Burj Khalifa will finally have to relinquish the title it has held for nearly a decade.

Hong Kong-Zhuhai-Macau Bridge

When it comes to massive engineering projects, the Chinese have everyone beat. Besides the majority of the tallest buildings in the world and Three Gorges Dam, the nation recently completed the Hong Kong-Zhuhai-Macau bridge. The 34-mile long structure opened in late 2018, providing direct ground transportation linkage between these three locales.

The transportation link consists of multiple oversea spans and an undersea tunnel. The project was certainly controversial, taking nearly 10 years to complete and massively overrunning the budget by about 10 billion yuan. It’s still a significant accomplishment. Previously, transit between Hong Kong and Macau took hours by ferry. Now you can travel between the two in just 30 minutes.

Gotthard Base Tunnel

This engineering marvel will be a bit hard to “see”. Like many tunnels, you won’t be able to look out your window to enjoy the sights, nor can you really get a good impression of the structure while transiting through it. But that doesn’t make it any less impressive.

The Gotthard Tunnel is the longest railway tunnel in the world. It is also the deepest transit tunnel ever constructed. Rather than snake your way through the Alps, you can now simply pass under them. The 35-mile connection between Erstfeld and Bodio, Switzerland allows greater freight capacity between northern and southern Europe. It also cuts the transit time through the Alps significantly, saving travelers 35 minutes between Zurich and Milan. With the completion of the Ceneri Base Tunnel, it should take just 2 hours and 45 minutes to get between the two cities.

The Egyptian Pyramids

I mean…who said the list has to be of all modern engineering marvels? The Pyramids at Giza stand as one of the most impressive ancient wonders. While we have modern construction methods, power sources, and materials at our disposal for our feats, they had none of these. Standing an impressive 450 feet tall, these constructions of giant stone blocks might be the most impressive of all, considering when and how they were constructed.

The Bailong Elevator

Literally, the “hundred dragons” elevator, the Bailong elevator takes you to the top of a huge cliff in the Wulingyuan scenic area. A UNESCO World Heritage Site, the sandstone formations in China’s Hunan province are a desitnation in their own right. Riding the tallest outdoor lift in the world is just icing on the cake. The Bailong Elevator clocks in at 1,070 feet.

The Chunnel

This one might be a bit ho-hum, given the impressive tunnel through the Swiss Alps, but transiting the Channel Tunnel (colloquially the “Chunnel”) by either car or rail is something I certainly hope to do someday. Opened in 1994, it was a pretty big deal. I remember being awed as a kid that there was a tunnel under the ocean. The 31-mile transportation link is now a mainstay of European commerce. Train travel between London and Paris or Brussels is a much more convenient option than flying. This wouldn’t even be an option without the Chunnel, as it is the only fixed link between the continent and England.

The cost? An enormous £9 billion. It was the most expensive construction project ever proposed at the time.

Langkawi Sky Bridge

This pedestrian bridge completed in 2005 is quite the sight. A single column stays the cables that support the bridge deck. It may not be the biggest, tallest or largest in any way, but it is still a very interesting and impressive structure. The setting is exquisite as well. The bridge lets you enjoy the grandeur of the hills and forest of Malaysia’s Langkawi Island.

The Panama Canal

One of the most amazing engineering feats of its time, the Panama Canal provided a shipping lifeline between the Atlantic and Pacific oceans. It still operates today, with well over 10,000 vessels per year making the passage between the two seas. The canal incorporated interior lakes and rivers of Panama, so the actual canal length is approximately 50 miles. There are a number of tour options available if you are interested in visiting this engineering marvel.

Machu Picchu

The how and the why of constructing a city near the top of a mountain peak escapes me, especially for a civilization that lacked even ancient inventions, such as the wheel. This Incan marvel is certainly a sight to see. I know multiple people who have gone to visit it. Unfortunately, it is such a draw that tourists are having negative impacts on the ancient citadel. Peru has begun testing limits on tourism to the city.

With ancient wonders, it is a double-edged sword. They are a boon for tourism, yet you’re faced with the constant worry of degradation of such amazing sites.

What I’ve Seen Already

The Great Wall of China has to be the most impressive ancient marvel that I’ve ever seen. Standing on its stone steps and looking out at the wall snaking across distant hills evoked such a sense of wonder. My other favorite is the Golden Gate Bridge. I pass over this multiple time per year, and it never fails to amaze me.

How about you…what impressive engineering marvels are you interested in seeing?