Commuters who use one of Tokyo’s most crowded subway lines outside morning peak hours are being rewarded with free noodles.

Tokyo Metro is offering commuters on the Tozai line, one of the network’s most crowded routes, free tempura and soba noodles for taking earlier trains to avoid the crush.

Around seven million people use Tokyo’s metro system each day and, of those, more than 1.65 million use the busy Tozai line, which literally means “east to west”.

The challenge runs from 21 January until 1 February.

If at least 2,000 commuters take an earlier train during the two weeks, they’ll get free tempura. If 2,500 do, they’ll get free soba noodles. And if 3,000 people take earlier trains to work they’ll get a bowl of free tempura and soba.

Takeshi Yamashita, a Tokyo Metro spokesman, told AFP: “This is our most congested line. We are always trying to ease the rush hour congestion.

“We hope this will encourage people to continue (taking early trains) to help ease the rush hour situation.”