What is eshima ohashi bridge?

The Eshima Ohashi bridge, often nicknamed the "rollercoaster bridge," is a concrete rigid frame bridge in Japan that connects Matsue, Shimane Prefecture and Sakaiminato, Tottori Prefecture. It is the largest of its kind in Japan and the third largest in the world.

What makes the bridge notable is its steepness. It was designed with a high gradient to allow ships to pass underneath. The Tottori Prefecture side has a gradient of 6.1% and the Shimane Prefecture side has a gradient of 5.1%. This steepness, combined with its length (1.7 km long and 11.3 m wide), gives it the illusion of being a very steep and intimidating climb, particularly when photographed with a telephoto lens, making it appear even more dramatic than it actually is. Despite its appearance, the bridge is safe and regularly used by standard vehicles.

The bridge's construction was necessary to replace a drawbridge, which frequently caused traffic delays due to the number of ships needing to pass through the canal. The design (https://www.wikiwhat.page/kavramlar/Design) allows unimpeded ship traffic while providing a direct route for vehicular traffic.