Motorists on the UK's most congested road spend an average of two and a half days a year sitting in traffic.
Taxi drivers try to avoid the worst offender - London's A406 North Circular Road from Chiswick Roundabout to Hanger Lane - "at all costs", says one firm.
Traffic data firm Inrix said drivers lost the equivalent of a week each to jams in 2018.
The Department for Transport (DfT) said it was investing in public transport to ease congestion.
Road users lost an average of 178 hours each to congestion in 2018 in total across all roads, Inrix said.
It estimated the value of the time lost at about £7.9bn or £1,317 per driver.
London's drivers lost about 227 hours each on average, compared with 190 hours in Belfast, 165 in Edinburgh and 143 in Cardiff.
'Avoid at all costs'
Traffic on the North Circular road between Chiswick Roundabout and Hanger Lane can start building as early as 04:30, according to taxi firm owner Manoj Teji.
Mr Teji, 51, who has lived and worked near the road all his life, said: "I can't see any solution to it."
He said the "bottleneck" road had had to cope with an increasing number of cars coming off the M4 and A40 in recent years, adding that drivers sometimes had no choice but to use the route, but where possible they avoid it "at all costs".
But Benjamin Menyhart, 27, who manages a hotel just off the A406 in Ealing, said although the road was quite busy, "I wouldn't have thought [it was] worse than some of the bigger routes in London."
Minicab driver Derek Kliger, 64, from Richmond said the road had not got any worse over the past three decades.
"It's a major circular route, and if people want to avoid the congestion charge it's the way you get from east to west London."
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Rod Dennis, from the RAC, said although congestion was seen by some as "a marker of a successful city" there was an "enormous cost" attached to it for drivers and for air pollution levels.
"Those cities that are best placed to grow will be those that are developing public transport systems that suit the needs of their citizens, and successfully decide the role the private car should play alongside these," he said.
Mayor of Greater Manchester Andy Burnham said Manchester needed powers and funding to tackle congestion.
"I've called on government to give us these powers now and let us get a grip of the congestion that plagues our city-region." he said.
A spokeswoman for the DfT said the government was investing £23bn into the UK's roads, with £2.5bn to support "innovative public transport schemes" to help ease congestion in urban areas.
Transport for London said it was taking "bold" measures to reduce congestion, including extending the congestion charge to private hire vehicles.
A spokesman said it was also looking to make sure companies doing road an utilities work around the capital were "better coordinated", and delivery companies "more efficient".
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