A sign reading "different temperatures on the same train" is seen on the platform floor on line six. (Photos provided to China Daily)

Beijing's subway has for the first time introduced carriages of different temperatures on the same train, said Beijing Subway on Thursday.

The subway's line six has since June 17 begun to introduce different temperatures throughout its trains. On line six's trains, the first 16 carriages are cold while the last 16 carts are warm, the subway company said, adding that the average temperature in the colder carts is around 25 C.

Passengers can now choose carriages based on their favored temperature, and 34 subway stations along line six now send out temperature reminders for passengers.

A sign reading "different temperatures on the same train" is seen on the platform floor on line six.

Connecting the city's sub center in Tongzhou district and Shijingshan district in the west, line six is a major public transport line crossing Beijing from east to west.

Line seven, which runs from Beijing West Railway Station in Fengtai district to Chaoyang district, is expected to become the next subway line to offer different temperatures in different carriages on its trains.