Sapporo has a subway and streetcar system operated by Sapporo City Transportation Bureau,

Sapporo Municipal Subway: city.sapporo.jp | Wikipedia

Official Sapporo Subway route map.

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Another official version of Sapporo Subway map.

[Map via city.sapporo.jp.]

Sapporo Municipal Subway map from Wikipedia.

[Map by Angaurits via Wikimedia Commons. Show full map.]

Sapporo Municipal Subway map by Sapporo Station.

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Sapporo Streetcar: city.sapporo.jp | Wikipedia

The official Sapporo Streetcar map.

Sapporo Streetcar from Wikipedia.

[Hisagi (氷鷺), via Wikimedia Commons. Show full map.]

Hokkaido Railway Company: jrhokkaido.co.jp | Wikipedia

Sapporo is the main hub for JR Hokkaido. The regional route map has an inset showing stations around Sapporo. This map shows the Chitose Line, which links Sapporo to New Chitose Airport.

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metro babel has an article on how Japan Rail (JR) works in Sapporo.

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UrbanRail.net has a combined Sapporo map with subway, streetcar, and JR Rail.

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Combined map by mapa-metro.com.

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uu-hokkaido.com has a combined subway, streetcar, bus map.

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Sapporo Subway & Street Car Map by hokkaidoguide.com.

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