Where should you go as one day trip from Sapporo?
1) Otaru
Speaking of the sightseeing spot near Sapporo, Otaru would be the most popular place for tourists. I cannot count how many times visited to Otaru, but quaint city view with the canal, orgel doh and old style buildings never make me bored at all. This small but unique town always give me beautiful impression.
I especially recommend to stroll the sidewalk next to the canal at sunset. Street lamps above the sidewalk are gas lighting rather than electric lighting because the light by gas is waving, which creates romantic shining.
In addition to its beautiful scenery, Otaru is also famous as a gourmet town.
Most Japanese domestic tourists expect to eat Sushi in Otaru, and enjoy cakes or chocolates at confectionery shops, such as “Letao” which also currently attract many tourists.
You can go from Sapporo to Otaru during looking at Japan sea from the train window.
Public trasprtation from Saporo to Otaru
Option 1:JR
Time: Approximately 30 minutes
Fare: JPY 640 (Free seating)
Option 2:Bus (Kosoku Otaru Go)
Time: Approximately 50 minutes
Fare: JPY 610
Otaru tourism association official website has more detailed information.
2) Jozankei
A hot spring which is the nearest from Sapporo and most familiar to Sapporo citizen is Jozankei Onsen. Public buses run from New Chitose airport (It takes about 100min) as well as Sapporo downtown (It takes about 75min), so tourists can individually go and enjoy the hot spring.
Most hotels in Jozankei are offering day trip hot spring plan even for the guests who are not supposed to stay at hotels. If you use the plan, depart from Sapporo in the morning and possible to return within same day even after enjoying hot spring.
Regarding time table of the buses or other details of Jozankei Onsen, please refer to the official web site of Jozankei tourist association 
Jozankei hot springs, blessed by the forest and the earth. | 定山渓温泉の観光ナビ「定山渓観光協会公式サイト」札幌の湯の杜 定山渓温泉の湯、食、遊びを目一杯楽しむためのガイド。お得な最新情報… via kwout
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Inter city bus pass http://www.hokkaidox.com/en/hokkaido-bus-pass is available until 27 Mar 2019. This bus pass covers the routes from Sapporo to Otaru and Sapporo to Jozankei. Once you get the pass (JPY 6,000 for 3 days pass, JPY 9,000 for 5 days pass), you can reach 20 cities and more than 100 travel spots in Hokkaido by local buses.
