The police have issued advice to cycling fans planning to watch the opening stage of the Tour of Britain tomorrow.
The race will start in Carmarthenshire before passing through Powys, including Llandovery, Brecon and Talybont-on-Usk, on Sunday before going onto the finish in Newport.
Dyfed-Powys Police have warned people hoping to see the race to expect delays on the road and there are signs along the route for the race which will finish on Sunday, September 9 in London.
Parents are advised to keep children away from the edge of the road and all fans are being told not to turn their back on the race.
Police have also told people not to block the cycle route or run alongside the cyclists.
The opening stage will be hosted by Carmarthenshire in the Tour of Britain's first visit to the county. The race will feature Wales' newly crowned Tour de France champion Geraint Thomas and his Sky teammate Chris Froome as well as other top cyclists.
To anybody travelling to the starting point at Pembrey, the police have advised walking or cycling along the Millennium Costal Path and that they will look after bikes in the station.
There will also be extra security at the country park along with bag checks so the public are being asked to only take the essentials.
Welsh Cycling CEO, Anne Adams-King said:“Welsh Cycling is pleased that Wales is hosting the Grand Depart for the 2018 OVO Energy Tour of Britain profiling our beautiful countryside and showcasing the City of Newport town centre.
“It’s fantastic for people to see four welsh riders in the peloton alongside some of the best riders in pro-cycling. An exciting start to the tour that will inspire a generation of youngsters to experience cycling.”
This year sees a strong line up for the race which will include Tour de France and Giro d’Italia champions Geraint Thomas and Chris Froome competing for Team Sky."