The REM is Montreal's Réseau express métropolitain, an automated light rail network whose first section opened in 2023 between the South Shore and downtown. Its driverless trains and enclosed stations give it a quieter, smoother sound than older heavy rail systems, which is part of why recordings stand out online. Clips like this one are shared by transit fans and editors who want an authentic modern train atmosphere for videos, podcasts and social posts about commuting, urban travel and Canadian city life, rather than a generic stock train noise.