Based on a casting call shared via Twitter, Outlander season four may be filming in Pollok Country Park again in mid-April 2018. From the casting call, the scenes may be filmed at night, involve Highland games, and revolve around the 1960s period. For fans that do try to attempt to see filming and meet actors, we hope that you are respectful of the cast and crew. Some of these scenes being filmed in various “rural” or park areas have kept fans far back from filming. Thanks, Kevin, for sharing the casting call.
— kevin (@d16nag) April 2, 2018
Source: Mad Dog Casting