The festivals will each explore a different theme, with sport, design, art, fashion, fitness, technology, film and music events on the cards. The pop-up campaign promises secret events, new retail concepts and a range of other brand experiences.
The first and current festival is centered around the theme of health and wellbeing. Brand experiences include fitness classes and interactive artwork from Frame; morning yoga and supper clubs from Pollen & Grace; and breakfast clubs and agony aunt drop-in sessions from Rebel Kitchen.
TfL is working with rental space company Appear Here to curate the festival activity.
Justin Brand, director of commercial asset management at TfL, said: "Since we launched Old Street Tube station as our pop-up retail destination [in April 2014], more than 200 retailers have set up shop there, bringing some fantastic services and products to the 23 million people who use the station each year.
"The new line up of retailers at the station will showcase some of the best brands around. The revenue that we generate from the retailers is reinvested into our transport network to deliver improved services for customers."
TfL announced a new partnership with Sport Relief on Tuesday (19 January).
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