<img src='http://i.imgur.com/rS7SnQJ.jpg' width='600px' alt='A company that had worked with Disney was originally supposed to help design Shanghai's Bund Sightseeing Tunnel. Instead, a local firm created the tunnel's psychedelic lights and trippy audio-visual effects. Length: 646.7 meters’ style=’float:left;padding:5px’ />
Maximum benefit for minimum effort — that’s good engineering.” Length: 1.65 kilometers (1.02 miles) Fast fact: The tunnel opens out to a dramatic view of Drammen Valley and has a beer garden, restaurants and open-air museum. Guoliang Tunnel: Safety not a priority here, it seems. Guoliang Tunnel (Henan Province, China) Before the construction of this impressive tunnel, the only way to access the village of Guoliang was via a narrow path carved into the side of the Taihang Mountains. In 1972, a group of 13 villagers decided to construct a tunnel, which they dug by hand. Three died during the construction process but the tunnel transformed the village and became a tourist attraction in its own right. “This link tunnel is beautiful and a tribute the tenacity of the villagers who built it,” says Thomas at Ramboll. “For me it emphasizes how tunnel construction can enhance the environment as well as bringing huge benefits for society. At the same time, one should remember the cost and the fact that several villagers were killed during construction.” Length: 1.2 kilometers (0.74 miles) Fast fact: The tunnel was built jagged and steep due to the village’s primitive tools, earning it the nickname: “The road that does not tolerate any mistakes.” SMART (Kuala Lumpur, Malaysia) “SMART is a combined road and flood relief tunnel,” explains Thomas at Ramboll. “It can be completely flooded to get rid of storm water and turned back into a road in a few hours.” The tunnel, the longest in Malaysia, was built to solve the problem of flash flooding in Kuala Lumpur.
For the original version including any supplementary images or video, visit 9 of the world’s greatest tunnels – CNN.com