Motorists have been warned to expect delays with several major events, including Belfast Pride, Féile an Phobail and the Let's Rock festival all taking place on Saturday.
A PSNI spokesperson said: "There will be a number of events in Belfast today which will cause some traffic disruption - while alternative routes will be available if you are travelling to or around the city, plan your journey in advance and expect some delays.
"In East Belfast, there will be some disruption between 10.15 a.m. and 1.30 p.m. due to a parade in the Hollywood Road and Newtownards Road areas."
This afternoon Belfast city centre is expected to come to a standstill for the annual Belfast Pride parade.
Up to 12,000 participants and up to 17,000 supporters are expected.
"There will be a series of road closures in the city centre as the annual Pride parade takes place between 11.30 a.m. and 2.30 p.m," the PSNI said.
Meanwhile in the west of the city road closures will be put in place in advance of the Michael Conlan Diego Alberto Ruiz fight in Falls Park.
"In West Belfast, the Féile organisers have applied for a road closure that will see the Falls Road close to through traffic from the Whiterock Road junction, to the roundabout at Milltown Cemetery between 10.30pm and 1am. This is to ensure the safe exit of people from the Boxing event being held in Falls Park," the PSNI advised.
And finally there will be some disruption in the south of the city as some of the biggest names of the 1980s including Heaven 17, Billy Ocean, Midge Ure, Marc Almond, Cutting Crew and Musical Youth come to town.
"In South Belfast, the Let's Rock concert organisers have applied for road closures on the Boucher Road which will most likely be implemented between 10 p.m. and midnight, again to ensure the safe exit of people from the event.
"With large numbers of people expected to attend these events, road users travelling in the city on Saturday should exercise great care and be mindful of pedestrians who may step off pavements or try to cross roads unexpectedly," the PSNI said.