The fire broke out Sunday afternoon in a vape shop on Union Street, next to the station. Flames engulfed the building, filling the frames of windows and shooting from the dome-capped roof.
The building, which dates to 1851, collapsed as it burned through the night, leaving only the facade standing.
Paul Sweeney, a member of the Scottish Parliament, likened it to the remains left after the Nazi bombing of Britain in 1940-41.
“It’s been completely wiped out, destroyed," Sweeney told the BBC. “The building is a gutted shell. It looks like something out of the Blitz."
There were no injuries reported, Scottish Fire and Rescue Service said.
People standing behind a police roadblock said they were shocked to see the ruins.
“It’s just so sad," Emma Reid said. "It’s such an iconic building.”
A cafe, fish and chip shop and hair salon were among the businesses wrecked by the fire.
“We are absolutely devastated to confirm that the shop has sadly been destroyed in the fire,” Sexy Coffee said on Instagram, though it vowed to rebuild.