We've placed this cache as close as we could to the houses that featured in the Beatles film Help! After finding the cache, keep heading up Ailsa Avenue to have a look. Depending on the time of day (weekday evenings and weekends) there is also a bonus trackable to find up this road, nestled amongst the Chelsea Tractors of St. Margaret's....OOH.
On 14th April 1965, the Beatles' first appearance in Help! was to be a scene in which their car dropped them in a residential street and they entered four adjacent terraced houses. The scene was filmed on this day at Ailsa Avenue in Twickenham, England.
The street was located near to Twickenham Film Studios, where the bulk of the film was made. Ringo Starr went into number 5. John Lennon went into number 7. Paul McCartney, number 9 and George Harrison, number 11.
A number of other street scenes were also filmed on this day at Ailsa Avenue. The interior scenes in the houses, which turned out to be an extensive living area, were filmed at Twickenham Film Studios.
Here's a link to a snippet of the weirdness that is Help! in the 1960s: https://www.youtube.com/watch?v=Yx_7xjpySK0