History's first bridges were simple support beams made of flat stones or trees designed to help people cross streams. They were nothing like some of the bridges of today. Some modern bridges are so fantastical that they don't look like they should even be standing. Keep reading to learn more about four bridges that seem to defy the laws of physics.

Gateshead Millennium Bridge, England

Gateshead Millennium bridge in Newcastle
Credit: Gannet77/ iStock

The Gateshead Millennium Bridge connects Gateshead Quays to Newcastle-on-Tyne's Quayside, each on opposite banks of England's River Tyne. Two curved pieces form the bridge — one serves as the deck where pedestrians and cyclists cross, and the other is support. The Gateshead Millennium Bridge is the world's first tilting bridge; the bridge allows ships to pass below through a tilting action that lifts the deck above the water during a four-and-a-half-minute process. When completely tilted, the gravity-defying Millennium Bridge looks as if it might fall into the river. Additionally, both parabola-shaped pieces of the bridge form the shape of an eye when the bridge opens, earning the bridge the nickname "Blinking Eye Bridge" in the United Kingdom.

The Gateshead Millennium Bridge has some awesome features that make it even more of an engineering feat. For example, the bridge cleans up its own trash. Each time the bridge tilts to let river traffic pass, any litter dropped on the deck automatically rolls into specially built traps on each end. Gateshead Millennium Bridge also runs on electric motors, making its operation environmentally friendly.

Duge Beipanjiang Bridge, China

Duge Bridge over canyon
Credit: ShakyIsles/ CC BY-SA

Duge Beipanjiang Bridge, one of China's most spectacular bridges, traverses the Beipanjiang Grand Valley at 1,854 feet above the average water level of the Beipan River, making it the highest bridge in the world, according to Guinness World Records. To give you an idea of how high the Duge Bridge is, San Francisco's Golden Gate Bridge rises approximately 220 feet above the water. The Duge Bridge was also the first to break the 500-meter height barrier and the first cable-stayed bridge to hold the "World's Highest Bridge" record. The Duge Bridge is so high that sometimes drivers see clouds below them while crossing the 4,400-foot behemoth.

Duge Beipanjiang Bridge connects China's Yunnan province to the Guizhou province, a notoriously rugged area with mountains, plateaus, deep river gorges, and canyons. In fact, three out of the world's five highest bridges are in Guizhou, with the Duge Bridge 227 feet higher than the next highest. Keep in mind that if you visit the Duge Beipanjiang Bridge, you cannot stop on the bridge to take photos and look around. Instead, plan to stop at one of either car parks on both sides of the bridge, so you take in a site that appears to defy all the laws of physics.

Moses Bridge, Netherlands

Moses bridge in the Netherlands
Credit: RONALD DUVERGE/ Shutterstock

Those who are intrigued by religious history know the story of Moses leading the Israelites out of Egypt. Moses and his followers are trying to escape the Egyptian army, but appear stuck by the Red Sea in front of them. Moses holds out his staff, and God parts the sea so that Moses and the Israelites can cross on dry land and escape the Egyptians. The Moses Bridge in Halsteren is an invisible pedestrian bridge. It creates an optical illusion that makes it seem as if pedestrians are walking through the moat of Fort De Roovere.

During the 17th century, the Dutch built a series of defensive fortresses, canals, and moats across their West Brabant Water Line to protect citizens from Spanish and French invasions. Fort De Roovere's shallow moat was one of these. The Dutch cleverly disguised a path to the fortress by building the bridge beneath the moat's waterline. If you visit Fort De Roovere, you can walk on the sunken Moses Bridge and look like you're walking through the water.

Eshima Ohashi, Japan

Eshima Ohashi bridge with traffic
Credit: mstk east/ flickr

Eshima Ohashi, a bridge that connects the Japanese cities of Matsue and Sakaiminato across the country's large Lake Nakumia, isn't the tallest, highest, or largest bridge in the world, but it looks scary for those who approach it, especially from the Sakaiminato side. Whether by foot or by car, as you approach Eshima Ohashi, it appears to go straight up and drop off into nothing, much like a roller coaster. The height allows for ships to pass below the bridge, and its appearance has more to do with vantage point than actual steepness.

At the same time, Eshima Ohashi is plenty steep. It is one of the tallest rigid frame bridges in the world. The Matsue side of the bridge has a 5.1 percent gradient, while the other side of the bridge is a 6.1 percent gradient. If you want to snap photos of the scary bridge, you can take the pedestrian and bicycle pathway to the center of the bridge, which is only a little over a mile long.