A 41-mile diversion has been put in place to guide motorists around a 50m (160ft) stretch of roadworks.
Traffic on the A352 usually takes just a few seconds to pass through the village of Godmanstone, Dorset.
But it is thought drivers who follow Dorset Council's official diversion - which strays into neighbouring Somerset - could take an hour.
The authority said it needed to provide an A-road alternative but most traffic would "undoubtedly" use other routes.
Its diversion notice - starting on one side of the closure and ending on the other - directs drivers via Charminster, Yeovil and Sherborne.
Godmanstone, which has a population of about 130 people, is part of a string of villages in the Cerne Valley which includes Minterne Magna and Cerne Abbas - famous for the chalk figure of a giant carved into a nearby hill.
The road closure was put in place while work is carried out to connect a new house to the sewerage system.
Resident Penny Gostelow described the diversion as "ridiculous" and said people "won't understand" why it is needed.
"I think it's absolutely ludicrous when there are other alternatives they could use," she added.
Roy Attfield, who runs a smallholding maintenance company, said: "Local people know the roads. There are plenty of B roads we can use.
"It's going to be a nuisance but I can get around it quite easily."
Most vehicles will be able make the journey around the closed section in under 10 miles.
A council spokesman said the five-day closure, due to start on Monday, was requested by Dorset Drainage Services.
He said the official diversion "has to be suitable for the type of traffic that would normally use the closed section".
"This is an A road so we have used other A roads for the diversion," he said.
"Smaller local traffic will undoubtedly use lower classified roads to bypass the closure."
HGVs travelling longer distances generally use the A37, which runs parallel to the A352.
Parts of the A352 and surrounding roads have been closed on several recent occasions for resurfacing or sporting events, including the Weymouth Ironman race.