All of the more than 1,200 tickets for Alicia Keys’ concert at Copenhagen’s 18th-century Royal Theater were sold in 16 minutes, organizers said Monday.

The 23-year-old R&B singer will perform June 16 on the theater’s main Old Stage, which dates from 1874. The Royal Theater has said it is the first time ever that a pop star would perform there.

Organizers said tickets went on sale online Monday and were sold within 16 minutes.

The downtown playhouse dates back to 1770. Its repertoire includes classical drama, ballets, operas and concerts by philharmonic and chamber orchestras.

Keys has been touring the United States with Beyonce and Missy Elliott on the First Ladies Tour.