The Channel Tunnel is considered one of the most amazing engineering feats of the 20th century.
The Channel Tunnel is a 50.45-km (31.4 miles) undersea rail tunnel linking Britain and France, under the Strait of Dover in the English Channel. The Channel Tunnel is also affectionately referred to as the Chunnel or Eurotunnel, and in French it is known as ‘Le Tunnel Sous la Manche’. Travel through the Channel Tunnel on a high-speed train takes around 20 minutes, and bypasses the sometimes inclement weather of the English Channel to deposit passengers safely on the other side.
In fact, there are three tunnels in the Channel Tunnel, two tunnels for trains, and a central access tunnel used for maintenance access and as an emergency escape route.
History and construction
Proposals to build an access tunnel under the English Channel date back to the 1800s, but construction on the Channel Tunnel didn’t begin until 1988. Workers on the tunnel faced a number of engineering problems as they had to deal with geological irregularities and the sheer amount of work involved in constructing a 31.4 mile (around 50 kilometer) long tunnel underground.
The Channel Tunnel had to be sturdy enough to withstand years of use as well as being well ventilated, and the engineers also wanted to allay concerns about the risk of fires in the tunnel with state of the art safety mechanisms, including the central escape tunnel.
Connecting the Tunnels
One of the most difficult tasks on the Channel Tunnel project was making sure that both the British side of the tunnel and the French side actually met up in the middle. Special lasers and surveying equipment was used; however, with such a large project, no one was sure it would actually work.
Since the service tunnel was the first to be dug, it was the joining of the two sides of this tunnel that caused the most fanfare. On December 1, 1990, the meeting of the two sides was officially celebrated. Two workers, one British (Graham Fagg) and one French (Philippe Cozette), were chosen by lottery to be the first to shake hands through the opening. After them, hundreds of workers crossed to the other side in celebration of this amazing achievement. For the first time in history, Great Britain and France were connected.
It took six years for the Channel Tunnel to be completed, and the safety systems were tested only two years later, when a fire broke out in 1996. The Channel Tunnel attracted a great deal of criticism, due to the fact that the construction ran heavily over budget, and many Europeans were concerned that the Channel Tunnel would not be able to turn enough of a profit to justify its construction.
The American Society of Civil Engineers has called the Channel Tunnel one of the seven wonders of the modern world, and as of 2008, it is the second longest tunnel in the world. It certainly streamlined and revolutionized travel between Britain and France, smoothing the way for visitors from both nations to travel rapidly and easily. Tickets are readily available for passengers who want to travel on the Eurostar passenger trains which service the Chunnel through Eurostar and various authorized agents.
When built: 1994
Depth: 40-75m below the sea bed
Timescale: Six years
Construction material: Concrete and steel
Capacity: 4 million cubic meters of chalk were excavated on the English side alone.