Transport for London (TfL) is challenging Londoners to get off the tube or out of their Uber and tackle the capital on foot.
To celebrate 10 years since the "Legible London" street signs, the blue information boards which show maps of the surrounding area, walkers are being asked to have a go at visiting as many locations as possible in three hours.
TfL already has walking maps showing distances between tube stations, but now it is encouraging Londoners to take things one step further.
By downloading the free Sporteering app and travelling to the sign next to the Royal Festival Hall sign on the Southbank, Londoners can start the challenge at any time.
Once the QR code at Royal Festival Hall has been scanned, the clock starts ticking. Participants need to plan their own route using the app, the signs, and their own knowledge of London's pedestrian-friendly routes to visit as many places as possible and return to the starting point within three hours.
The top three high-scorers will win a pair of tickets to see the new musical version of The Wind in the Willows at the London Palladium.
But don't worry if you don't manage to get into the winning trio, because TfL will be sending a certificate to all participants.
"This event is a great way to show everyone who lives, works or visits the city how walkable it is, and encourage active travel," said Ben Plowden, director of surface strategy and planning at TfL.
The event is in association with British Orienteering, which hopes to encourage more Londoners to brush up on their basic navigational skills.
Jennie Taylor, communications officer of British Orienteering, said: "Our aim is to raise the profile of orienteering skills across the country and encourage people to get involved in orienteering related activities in a new and exciting way."