Construction of this Gothic chapel began in 1447 during the reign of Emperor Frederick III, but it was later massively renovated. Today, the Burgkapelle hosts the Hofmusikkapelle, an ensemble of the Vienna Boys' Choir and members of the Vienna State Opera chorus and orchestra, which performs works by classical and modern composers. Send written applications for reserved seats at least 8 weeks in advance. Use a credit card; do not send cash or checks. For reservations, write to Verwaltung der Hofmusikkapelle, Hofburg, A-1010 Vienna. If you failed to reserve in advance, you might be lucky enough to secure tickets from a block sold at the Burgkapelle box office every Friday from 11am to 1pm or 3 to 5pm, plus Sunday from 8:15 to 8:45am. The line starts forming at least half an hour before that. If you're willing to settle for standing room, it's free.