Amid a plan to move the 2020 Summer Games' marathons from Tokyo to Sapporo due to concerns over extreme heat, the games' organizing committee is considering starting and ending the events in Sapporo's Odori Park, several sources said Sunday.

The new marathon course will be based in part on the annual Hokkaido Marathon in which Odori Park, located in the center of the city, also serves as the starting and finish lines.

The park is being considered in place of Sapporo Dome, one of the International Olympic Committee's candidates, as it presents various logistical challenges such as narrow entrances and exits and the absence of a running track.

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Following the IOC's sudden announcement on Oct. 16 regarding the venue change and with less than 300 days until the games kick off, organizers decided to plan the new course based on the route used for the Hokkaido Marathon rather than an entirely new course.

The plan may take further shape during a special session of the IOC Coordination Committee meeting starting Wednesday in Tokyo.

Whether to use part of the new marathon course for the race walking events is also under consideration, as height fluctuations in the vicinity of Sapporo Dome make it unsuitable for the sport. An extended loan of the stadium, which is already due to host Olympic soccer matches, would also be required.

Odori Park, on the other hand, may lead to a decrease in ticket revenue as it lacks the space for large-scale spectator seating.