Police are warning motorists of potential congestion on the A30 in the Okehampton area this summer.
The temporary closure of Sourton Service Station for refurbishment is likely to cause congestion at Belstone Services in the coming weeks.
Traffic signs are in place warning motorists to slow down, including one at Whiddon Down, the junction prior to Belstone Services.
Inspector Mark Sloman, Sector Inspector for West Devon, said: “We are concerned the increased traffic at Belstone Services will create dangerous queues westbound on the A30 at the Okehampton junction.
“The junction is on the brow of the hill, not giving much warning for motorists to slow down, and we are urging motorists to take extra care when travelling on this section of the A30 the summer.”