Spokesman Erik Krikke of the city's historical center said the archive -- which contained photos, drawings and erotic texts with a connection to the city -- may have been taken home "accidentally" by an employee or visitor.
"We're hoping that someone will say 'Hey, I have that in my attic' and bring it back," he said Thursday. "No questions asked."
Krikke said the collection was small enough to have fit in a moving box.
Mayor Ferd Crone of Leeuwarden, 87 miles (140 kilometers) north of Amsterdam, told local media he had been unaware of the collection's existence and was surprised it was gone.
Krikke said the bulk of the archive had been assembled by a "fanatic" curator at the historical center, mostly during the 1960s and '70s. Items such as pictures by local photographers and artists would be difficult or impossible to replace.
The collection included a copy of the rare February 1998 edition of Dutch Playboy, Krikke said. It featured girls from each of 11 Dutch cities along the route of the country's most beloved ice skating race, the Elfstedentocht. One of those girls was from Leeuwarden.
Asked whether he thought it was unusual for the town to have a pornography collection, Krikke said "yes" -- and that made the loss greater.
"Actually, we don't have one anymore," he said.
Local events | Contests | Headlines at a glance
