Northern Pacific No. 25 is a class Y-1 2-8-0 it was built in 1899 by the Schenectady Locomotive Works for the Northern Pacific railroad as #25.
It worked on the Northern Pacific's Butte Mountain Division over the Continental Divide between Butte and Whitehall, MT.
When the locomotive retired it was donated to the City of Butte, MT, in 1958, it is on display adjacent to the Civic Center where it sits today.