There are six trains per day running in both directions, with the fastest journeys taking 3 hours 58 minutes.

[1] The service commenced as the limited express Ōzora (おおぞら) on 1 October 1961, operating between Hakodate and Asahikawa using KiHa 80 series DMUs with one return working daily.

In October 1980, following the opening of New Chitose Airport, services were reorganized, with just one return working daily between Sapporo and Kushiro.

From October 1981, the train was rerouted via the Sekishō Line, reducing journey times by approximately one hour.

On 27 May 2011, the Super Ōzora 14 service from Kushiro to Sapporo was brought to an emergency stop inside the 685-metre-long (2,247 ft 5 in) No.