Not normally open to the public, Acton Depot open weekends are a fantastic opportunity to see some of the hundreds of thousands of treasures stored in the working\u00a0museum storehouse. What to expect The depot open days take place three times a year, in April, June and September. This September's theme is Transport & Stories - tales of the people who worked on London's public transport network (both past and present) and the passengers who travel on it. Check out the many historic vehicles, posters, signs and maps in the collection, including the original versions of Harry Beck\u2019s iconic diagrammatic Tube map, first issued 90 years ago. There'll also be a series of themed activities for children and adults alike, including expert talks and special displays, access to the small objects store, plus a Lego station to build your own transport-inspired creations. Tickets for Acton Depot Open Weekend Tickets must be booked in advance and cost ; children under 18 go for (and free for under 3s). Children 15 and younger must be accompanied by an adult.