The annual Bike the Bridge event in Windsor has been cancelled due to "security concerns."
Hundreds of cyclists were to bike from Windsor to Detroit and then tour Motown next month.
An announcement on the event's website broke the news to cyclists.
"Due to circumstances beyond our control, the 2013 Bike the Bridge event is cancelled. The International Bridge Company was unable to provide a date to cross the bridge due to security concerns. We look forward to 2014," the posting said.
Calls placed by CBC Windsor to Ambassador Bridge officials were not immediately returned.
However, while Bike the Bridge organizers claim Ambassador Bridge officials told them security concerns led to the cancellation, Rashida Tlaib, a Democratic member of the Michigan House of Representatives, says she checked with the U.S. Department of Homeland Security and is confident "there is no credible threat to the bridge at this time."
Bike the Bridge is the only day of the year pedestrians of any kind are allowed on the Ambassador Bridge.
Once across the bridge, cyclists can tour the host city. Long and short tour options let participants learn about the region and enjoy the local offerings.
Detroit was to play this year's host.