Due to take place on 20 March, the event promises live music, swing dancing, food, drink and ‘surprises’. A total of 4,000 people will be granted entry.
A number of London parks, squares and high streets will form part of four, two-mile trails leading to the party’s secret location. Those that wish to attend will have to solve a series of riddles and tasks to find the hidden spot, with the Mayor hinting at challenges including dance routines, taste tests and herding sheep.
Clues will reveal themselves in surprising ways, such as a message in a bottle or an actor in disguise.
Interested groups can register for tickets via Eventbrite.
Search Party is being organised by the not-for-profit group Sing London as part of Find Your London, a new festival that will take place from 18-28 March. Other free or cheap activities planned around the event include yoga in the park, cycle trails, beekeeping workshops and an Alice in Wonderland Tea Party.
Find Your London aims to get Londoners exploring their city further, and has been organised in partnership with 44 organisations. These include the Design Museum and Woodland Trust.
Boris Johnson, the Mayor of London, said: "My new festival celebrates our city’s great outdoor space from our much loved woods and parks, to our bustling high streets and town centres. There are a smorgasbord of festival events from searching for clues to locate secret parties, launches of new markets to historical tours of our river sides.
"London is without a doubt one of the most fascinating cities on earth and Find your London is the perfect excuse to get out and explore the fantastic things to see and do in our glorious city."
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