State-owned China Railway Investment Corp has opened tenders for 351 bullet trains, which it claims is the largest train order in history.

The contract requires 228 bullet trains able to reach a maximum speed of 350 kilometers per hour, and 123 trains capable of 250 kilometers per hour, said CRIC, a subsidiary of China Railway Corp.

Experts estimate the tenders could be worth more than 66 billion yuan ($10.6 billion). They are open to China-based makers only, which have the necessary manufacturing licenses for high-speed trains.