For an up-close-and-personal (and gut-dropping) view, bridge tours take visitors to the top of one of the towers. Take note, China bridge barons.The bridges of Madison County have nothing on this 112-year-old National Historic Site of Canada, which became the world's longest covered bridge only after two spans were destroyed by river ice in 1920, prompting replacement and a roof (covering helps prevent rot on the central wooden trusses). This article introduces the design of the main bridge and its For the main truss, steel Q420qD, Q370D and Q345qD are adopted; for deck system, Q345qD is mainly adopted, which corresponds to 420 and 355 grade steels. Completed in 1998, the record-setting central span 213 feet above the sea makes up over half its total 12,831-foot length; by comparison, the Golden Gate's central span is only 4,200 feet. But in the race to build the biggest and baddest bridges of them all, record-hungry China tends to dominate in hard stats.Five out of the top 10 suspension bridges are there, for instance. This list of the longest arch bridge spans ranks the world's arch bridges by the length of their main span.The length of the main span is the most common way to rank bridges as it usually correlates with the engineering complexity involved in designing and constructing the bridge. If it's anything like its distant cousin the Pont du Gard aqueduct, it will stand for hundreds more. Running parallel to the Yangtze River past lowland rice paddies, most of the span acts as an elevated railway, similar to the El in Chicago, though a 5.6-mile section does act like a traditional bridge, crossing the Yangcheng Lake in Suzhou.Time, fortitude and frigid cold are the only tools needed to build an ice bridge.
This is a private tour priced by group,300 USD per group not per adult.

Wulong Karst Geographic National Park was the second tour attraction inscribed on World Heritage List by UNESCO in Chongqing, the first one is Dazu Rock Carvings which mostly dedicates the cultural and historic side of Chongqing. The continuous steel truss arch bridge with tie girders has a height of 142 m (466 ft) from middle supports to arch top, main span of 552 m (1,811 ft) and a total length of 1,741 m (5,712 ft). For web members, box, H and I-shape sections are adopted with box section depths of 1240-1440 m and plate thickness of 24-50mm. Though arch bridges are still popular today, they're usually built with modern materials like steel (see: Chongqing, China's Chaotianmen Bridge, at 5,712 feet the longest arch bridge span, period). If you ever find yourself in Hunan, China, rent a car and drive the Jishou-Chadong Expressway: 18 tunnels under the Wuling mountains that culminate at the Aizhai Bridge, a gut-churning 1,150-foot-high suspension bridge over the Dehang Canyon. Don't miss Travel + Leisure's guide to the There's a perfect beach for every week of the year.
The design was chosen due to the lake's unstable bed and the curved nature of the roadway (a common problem for the area, which would explain why the state is home to four of the five largest floating bridges in the world). Planning a getaway? Which is a shame, considering some masonry arch bridges (brick and/or stone) are so mathematically precise, not to mention beautiful, they could stand without mortar. One of the most dangerous (and unique) bridges on this list, it is also one of the only ways to service the ExxonMobil hub of Point Thomson.Though bridges are one of the greatest examples of human engineering, they are hardly a creation unique to man: rock archways hewn by Mother Nature (usually by erosion) likely provided inspiration for our brick-and-steel masterworks. The country is home to three of the longest natural bridge spans in the world, including the 400-foot stunner over the Buliu River near the border of Vietnam. Built as a private bridge by a coalition of residents desperately in need of a direct way across the Saint John River -- 3 cents for a pedestrian; 6 cents for a horse and wagon -- it's now a regional icon open to all, beloved enough to get its own Google Doodle.