not much doubt about it . . . . . . . . . !
Have just applied ruler to map, as we always used to . . . . . !
Wigan to Blackpool 20.0 nm
Manchester 17.5 nm
Woodvale 15.5 nm
Liverpool 15.0 nm
Barton 9.5 nm
The new "Warrington International" is probably even closer to Wigan, but is not shown on my quarter mil map ! My estimate is probably about 7.0 nm.