At every overseas whistle stop these days, China's leaders peddle their nation's high-speed rail construction as a route to modernization. Now, the country's train salesmen can claim a big endorsement from a trio of World Bank experts who laud its discount construction costs.

At more than 10,000 kilometers (6,200 miles) of track by the end of last year, the report says China's system "far exceeds" the high-speed rail capacity of any nation, with another 12,000 kilometers under construction. Flush with words like "remarkable" and "world class," the report says China's system operates at high volumes while maintaining good reliability and comfort for passengers.

Topping it off is the price tag: "This has been accomplished at a cost which is at most two-thirds of that in the rest of the world," says the report.

World Bank senior transportation specialist Gerald Ollivier and two bank consultants who authored the report estimated infrastructure unit costs for China's fastest trains at around $17 million to $21 million per kilometer, compared with $25 million to $39 million per kilometer in Europe. Construction costs for a high-speed line planned in California, it said, may be as high as $52 million per kilometer.

The term "high-speed rail" typically refers to trains built to run at speeds exceeding 250 kilometers per hour (155 miles per hour), though some of China's are designed to reach 350 kilometer per hour.