The two-day metal music festival, organized by Metallica, opened Saturday with a few ticketing and shuttle snafus, The Detroit News reported Sunday.
Concert-goers waited in lines for as long as 2 hours to get tickets and to board shuttles -- the only mode of transportation to the Belle Island venue -- the newspaper said. Lines snaked through the Cobo Center lobby and down several city blocks.
Ticket handlers Front Gate Tickets said they doubled their staff for Sunday.
Metallica was scheduled to perform Sunday, but performed an unannounced set of their entire debut album, "Kill 'em All," the Detroit Free Press reported.
The band was billed as dehaan, the only band on the schedule for which no information had been provided.
In an interview last week about the band, Metallica drummer Lars Ulrich said dehaan was "a buzz band from Baltimore."
"We hope you knew," singer James Hetfield told the crowd during the performance. "We hope you were surprised, too."
Red Hot Chili Peppers closed Saturday's events. Metallica, Death and the Deftones were on the schedule for Sunday, the Free Press said.