The inveterate urban explorers at Southern California Transit Advocates came up with a pretty cool Day After Thanksgiving outing this year: they will ride all four Metrolink lines on Friday, and for just $7.25 a person using the service's friends and family 4-pack discount. They leave Union Station on the Orange County line at 8 a.m., and arrive back for good on the Antelope Valley line at 7:50 p.m. There are optional exit points through the day and a lunch break, and if you care to join en route you can follow the progress on Twitter. This year's exercise in transit riding even made Metrolink's official newsletter.

Previously on LA Observed:
Transit night owls