If you have a fear of heights, please have your medication handy while watching. Introducing the 20 most dangerous bridge tops in the world that will make your hands and feet tremble.

The Zhangjiajie Glass Bridge, located in Zhangjiajie, Hunan Province, China, opened in 2016 as the world’s longest and highest glass-bottom bridge. This thing stretches 1,410 feet long and 20 feet wide, sitting about 980 feet in the air. It links up two mountains in the Zhangjiajie National Forest Park, and they say about 800 tourists can stroll across it at a time.

The bridge was cooked up by Israeli architect Haim Dotan, and it’s made of over 120 glass panels. It’s held up by four massive pillars, and get this, they even have three long swings underneath! They’re also planning a bungee jump setup at 935 feet. Mad, innit?