This line, last known as the Jamestown, Westfield and Northwestern Railroad, can trace its roots back to 1881, when the Mayville Extension Railroad built a line between Mayville and Chautauqua in New York, on the north side of Chautauqua Lake. The line was subsequently extended as its owners underwent various purchases and reorganizations up until 1913, when the JW&NW purchased the entire line and operated it up until its abandonment. During its time under the JW&NW, it was electrified for both passenger and freight service. However, passenger operations ended on November 30, 1947, after which the line became diesel- and freight-only until its abandonment in 1950.
A rough timeline of the the JW&NW between Jamestown and Westfield:
Jamestown Mayville Chautauqua Westfield
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1881 |----- MERR -----|
1887 |----- CLRy -----|-Purchased CLRy-|
1894 |----- Reorganized as J&LE -------|
1899 |------ Reorganized as J&C -------|
1902 |--Leased JC&LE--|---- JC&LE ----|
1907 |---- Buffalo & Lake Erie Traction Company -------|
1913 |---- Jamestown, Westfield & Northwestern --------|
1950 |-------------- Abandoned ------------------------|
Today, most of the original right-of-way can be traced, except for in a few areas, as noted on the map below. The very southern end of the line, in Jamestown, was used most recently to serve a few scrap dealers; this last remaining segment was most likely abandoned when Conrail placed its mainline through Jamestown on "out of service" status. That mainline has since been reopened as the Western New York & Pennsylvania Railroad, but the JW&NW was not included in that reopening and remains unused.