A fire raced through the historic KB Hallen multi-purpose arena in Copenhagen, Denmark Wednesday, destroying most of the 73-year-old building.

The fire is believed to have started when overheated light bulbs caught on fire near cardboard boxes just hours before an erotic trade fair was to open. A number of people preparing for the fair were sleeping in the building when the fire started. Most escaped unharmed but at least two were hospitalized with smoke inhalation.

The venue, which opened in 1938, had hosted tennis tournaments, boxing matches and concerts — featuring such renowned names as Bjorn Borg, John McEnroe, the Beatles, Rolling Stones and Bob Dylan.

Smoke billowing from the fire formed a large plume that was visible over most of Copenhagen. The Copenhagen Post reported police were advising residents near the fire to stay indoors and close their windows to avoid being exposed to the toxic smoke.