Want to get from Paris to London in just over two hours? How about Barcelona to Madrid in two-and-a-half?

Take the train.

As roads and airports get slower, trains are going ever faster. How fast? Think 125 mph (201.12 km/h) and up, according to the International Union of Railways. And more are on the way.

But the cost -- say, $20 million a mile -- makes adoption a pricey project.

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Still, once they're in place, these trains exceed the speed of automobiles by two or three times. And while that can't compare with jet aircraft, the time spent traveling can be equal or less when you factor in the time going from city to city, especially when both are in the same region.

There are already significant high-speed corridors in France and Japan ready to serve customers. The dominant systems are the French Train � Grande Vitesse, the Japanese Shinkansen systems, the German Neubaustreke systems, and the Spanish National Railways.

In Japan, the Shinkansen high-speed train corridor reaches from Fukuoka through the mainland, to Tokyo, and on as far north as Hachinohe. The Japanese have excelled in both standard multi-engine trains and shorter maglev (magnetic levitation and magnetic roll forward) trains.

Their high-speed Shinkansen trains have become a world model. They travel at just below 200 mph (321 km/h). Each train of their 500 series cost $40 million. The Japanese tunnel through mountains rather than climbing grade, and it is a major cost factor. The Shinkansen system will be fully operational by 2009.

French travelers have many options with the country's TGV line out of Paris. The cost of construction is averaging $21.5 million a mile. It is minimized by using steeper grades rather than tunneling. France just grabbed the world record for standard-gauge rail trains with its TGV V150.

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"This speed record represents a major technological and human achievement," said Anne-Marie Idrac, the CEO of SNCF, France's rail system. "The results of tests conducted aboard the V150 train set enable us to envisage a highly promising future in the domain of very high-speed rail transport."

Germany is also working to increase speeds with a series that they call Neubaustrecke routes with new train cars. Technology company Siemens is helping with both the cars and the signaling and control systems.

And in Spain, RENFE is planning a Barcelona-to-Madrid run that will, when it opens, accomplish the trip of 375 miles (603 km) in two-and-a-half hours at a speed of up to 230 mph (370km/h), a quarter of the time it takes by car.

A high-speed line already exists between Madrid and Seville using French-style trains. The Spanish government is serious about the project: It has allocated about $31 billion through this year for work on it. The majority of the work on these projects is divided between the Spanish Talgo/Bombardier consortium and Siemens.

Other European high-speed efforts include the Netherlands high-speed line between Amsterdam, Rotterdam and Antwerp. It is expected to begin operating this fall as well, after a long wait. The trip from Brussels to Amsterdam will only take one-and-a-half hours. Other systems exist in the U.K., with its Intercity lines, as well as Italy, Finland and Portugal.

The Japanese and European enthusiasm for high-speed trains has spread to China and Malaysia. A proposed train by YTL will link Singapore and Kuala Lumpur, the Malaysian capital.

"What takes about four-and-a-half hours by road and 50 minutes by plane, you could do in less than 90 minutes by train," says Francis Yeoh, the chief executive officer of YTL. South Korea and Taiwan have already bought into their own high-speed system.

The car-dominated United States is a clear laggard. The only operational near-high-speed train is Amtrak's Acela Express.

And it is hardly high-speed. On paper, it can go 150 mph (241 km/h), but it normally averages less than 60 mph (96.5 km/h) due to track limitations. A trip from Washington to Boston takes about six-and-a-half hours. That's about the speed of the now-historical New York-to-Chicago 20th Century Limited.

Still, maglev trains are being developed in Pittsburgh and Las Vegas. Atlanta is also proposing a maglev from Hartsfield-Jackson Atlanta International Airport. San Diego is contemplating a $10 billion, 80-mile (128 km) run of maglev trains for airport transportation.

Also in California, a $40 billion high-speed corridor has been proposed from San Francisco to Los Angeles and San Diego. So far, $40 million has been spent on planning, and a $9.95 billion bond is up for approval this year. Political insiders say, however, that passage is unlikely.

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