The blaze began Wednesday morning in the Suit Corner, owned by Gary Ginsberg. Last year, Ginsberg's uncle sold the Shirt Corner building on the other side of the intersection to a developer. That building collapsed last month during demolition.
"All these years at Third and Market, going down to an end," Ginsberg said as he watched the fire. "I just can't believe this is happening. . . . It just went up in smoke."
The intersection on one of central Philadelphia's main arteries used to be home to two other Ginsberg family businesses, the Tie Corner and Pants Corner.
"At one point they were a highlight of this part of the city," Pat Hillman, an employee at Art Supplies, another building at the intersection, told the Philadelphia Inquirer.
The fire is believed to have begun in a display case and spread quickly. Wayne Artez, who manages the nearby High Street on Market restaurant, called it a "blazing inferno."
Suit Corner occupied a four-story building dating back to the 19th century and a one-story extension.