More than 300 road accidents were caused last year by vehicles hitting deer in the road in Sussex.
Now new signs have been installed by the council warning drivers to be on their guard.
East Sussex County Council has worked with the Ashdown Forest Conservators to place larger and more prominent signs on the A22 at Wych Cross and Nutley.
The section of the A22 bordered by the new signs has had more traffic collisions involving deer than any other comparable stretch in Britain.
Last year Ashdown Forest Rangers dealt with 336 collisions with deer on roads in and around the forest - a huge rise on the previous year.
Injured About half the deer involved in these collisions are still alive, but very gravely injured, when the rangers arrive.
The new gateways comprise of two large, highly visible, yellow panels which form the background to a triangular, red-bordered deer warning sign and a plate stating the distance covered.
Councillor Matthew Lock, cabinet member for highways, said: "We have had deer signs on the A22 for many years but despite this there have been a large number of accidents involving deer.
"These new gateways will increase awareness of deer on this particularly affected stretch of road.
"However, drivers should remember that deer may appear on any of the roads in and around Ashdown Forest."
ESCC hope to erect warning signs between Wych Cross and Forest Row later in this financial year.