Philippe Gilbert has taken the Strava KoM on the Côte de La Redoute while out filming for a documentary.
The climb is one of the defining features of Liège-Bastogne-Liège, which Gilbert won in 2011, and the Belgian lopped 17 seconds off the previous best time, riding the short, steep ascent in four minutes 25 seconds.
Averaging 20.9km/h, the only rider to break the 20km/h barrier up the climb, Gilbert took the KoM off Ag2r La Mondiale's Romain Bardet, who had the previous best time of 4-42.
The Lotto-Soudal rider was out on his "childhood roads" filming for a documentary, riding over 100km in three and a half hours.
"Yesterday I had a filming day for my documentary and we spent a day in Belgium. My brother challenged me to take the best time on La Redoute. Try to beat it!" Gilbert said.
Gilbert's 2020 season is geared around an attempt to win Milan - San Remo, rescheduled for August 22, which would see the 37-year-old claim all five different Monuments, joining his compatriots Eddy Merckx, Roger De Vlaeminck and Rik Van Looy in the select group of riders who have achieved this feat.
The Belgian has had an eventful lockdown as he bides his time waiting the resumption of the racing season, having been fined for breaking Monaco’s coronavirus lockdown rules and riding outside in April.
Gilbert said he had intended to ride laps of an 11-kilometre loop but was issued a €100 (£87) fine for violating the quarantine rules.
Authorities in Monaco and France had banned outdoor riding in an attempt to slow the spread of coronavirus, with the dozens of pros who live in the area forced to find other ways to maintain their form.
The Belgian said at the time: "We had found an 11km lap that we did three or four times in a row and that allowed us to get some fresh air for an hour.
"At one point, we were arrested and I was fined €100. By virtue of our status, there is no free pass. Every citizen is equal before the law. Just because I won Paris-Roubaix last year doesn’t mean I have more rights than another person. As a public figure, we must lead by example."
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