While apparently set in Seattle, filming is mostly done in Los Angeles. The fire-station's exterior establishing shots are from the Seattle Fire Department's actual Station 20 (there is no real-world 'Station 19'), located on 15th Avenue West on Queen Anne's west side.
This is the second Grey's Anatomy (2005)'s spin-off series. Likewise set in Seattle, the fictional 'Station 19' is located just three blocks from the fictional 'Grey Sloan Memorial Hospital'. The first spin-off, Private Practice (2007), is set in Southern California.
Jay Hayden (Travis) and Jaina Lee Ortiz (Andy) are dating in real life
Before starring in Station 19 and its parent show Grey's Anatomy in 2018 as Pruitt Herrera, Miguel Sandoval appeared in a 2012 episode of Grey's Anatomy as Hank, the partner of a patient undergoing a liver transplant.