A map of the Massachusetts counties as they appeared between 1912 (when Hyde Park was annexed by Boston) and 1938 (when the Quabbin Reservoir was created)
This file was derived from: Massachusetts county map 1938 to 1947.svg
Redrawn county lines informed by The Newberry Library
Original work by User:Awmcphee. This version by User:WallAdhesion.