Drivers have been warned to expect delays on a main road through the Brecon Beacons this evening.
A large of flock of sheep will be moving for around two miles down the A4067 near Ystradgynlais.
The sheep will be moving from around Dan yr Ogof show caves to Penycae along with main road, and drivers have been told to expect delays of around 15 minutes between 6pm and 7pm.
The warning, which was issued on Facebook, said: “There will be tired sheep, farmers and especially sheep dogs, so here are some tips”.
The post which can be seen in full here, advised drivers to pull as close to the side of the road as they are able to, and to turn engines off for all vehicles when they see the “front warning vehicle” approaching.
The post, which also advised motorists to remain in their vehicles, said: “Do take pictures from a distance. Standing in the road will scare the sheep and prevent them passing quickly and safely.
“You may be asked to help by blocking a gateway or side road. This will be greatly appreciated and know that you are making a massive contribution.
“Do not move off until sheep and dogs are well passed you. Sheep dogs and farmers will be very focused on the sheep. Neither sheep nor dogs have studied the Highway Code and all will be off lead.
“We appreciate this may cause you minor inconvenienced and your patience will be greatly appreciated.”