The man on the bike was filmed navigating past the marchers in Derry / Londonderry as he cycled onto the Waterside end of the upper level of Craigavon Bridge.
The unusual encounter was captured by a local person.
Neither party seemed at all phased and the cyclist continued on his way as the marchers walked on.
The short clip has been shared thousands of times on social media since it was captured at the weekend in the city.