Twelve people have admitted causing a public nuisance following a so-called Halloween "ride out" involving bikers in Leeds.
The 11 men and one woman were arrested after the incident on October 31.
Motorbikes and quad bikes congregated in Kirkstall Road before a large number were ridden through the city centre, including through pedestrian areas and shopping arcades.
At Leeds Crown Court on Thursday, they each admitted they "caused a public nuisance by participating in a large scale procession of motor bikes and similar vehicles that rode around Leeds in a manner that interfered with the comfort, enjoyment and safety of the public".
Judge Geoffrey Marson QC bailed them to appear before him again on July 10, when they will be sentenced.
The judge said giving them bail "was no indication as to sentence".
Those who pleaded guilty were:
David Armitage, 26, of Brookfield Road, Leeds; Omar Ahmed, 24, of Stonegate View, Leeds; Ashley Benson, 25, of Whingate Road, Leeds; Michael Clough, 27, of Torre View, Leeds; Ben Colley, 26, of Butterbowl Road, Leeds; Dean Fawcett, 28, of Intake View, Leeds; Nicholas Flaherty, 29, of Prospect Street, Leeds; Rachel Gibson, 29, of Grange Park Walk, Leeds; Joshua Hawley, 22, of Mead Grove, Leeds; Dylan Lockwood, 23, of Torre Grove, Leeds; Adam Nicholson, 26, of Bellmount Close, Leeds, and Anton Rojas, 26, of Skelton Avenue, Leeds.
Colley also admitted driving while disqualified and without insurance. Flaherty admitted perverting the course of justice.
Another defendant - Hernani Banza, 27, of Shafton View, Leeds - denied the charge of causing a public nuisance and will go on trial at Leeds Crown Court on November 28.
A fourteenth defendant - Jamie Ayres, 26, of Lupton Avenue, Leeds - has yet to enter a plea to the same charge. He is due back at Leeds Crown Court on June 8.
Banza and Ayres were both given bail by Judge Marson.