Anvil Centre as Tannhauser Industries
Caitlin goes to her mother's office for help with her freezing powers.
Source: What's Filming
“Monster” Filming Locations
Barry faces off against a giant monster that is terrorizing the city while Caitlin heads to her mother’s lab to find some answers about her new condition.
The Flash episode “Monster” was filmed in Vancouver, New Westminster, & Maple Ridge in Canada.
Homer Street (between Georgia & Dunsmuir) as Harbor District Attack
Barry heads to where a giant monster is attacking the harbor district and helps Iris save some people from a bus.
E-One Moli Energy as Tannhauser Industries (lab)
Caitlin's mother Dr. Tannhauser runs some tests on her cold powers.
Alley (south of Bute, west of Pender) as Alley Investigation
Barry is tagging along with Julian's investigation into the monster attack when the monster appears again and he has to save Julian from another transformer explosion.
Homer Street (between Robson & Georgia) as 2nd Street Promenade
Barry sets up a trap for the monster only to learn it is a hologram.
Vancouver Central Library as Second and Fulton
The Flash stops the police from injuring someone by shooting through the monster hologram.
1133 Melville Street as Hamilton Building
Julian Albert tracks the monster's creator into an empty building and the Flash arrives just in time to stop Julian from shooting the kid.