Did you enjoy your stroll I hope the weather was good and you find one of the nearby benches empty while you calculate the following easy formula.

You will find these letters in the five stages they reveal the numbers required to complete the coordinates for the bonus cache

A George Sparkes will tell you

B A knight knows this

C A lady holds this number

D is in The hall

E The artist knows this

N 51° 28.EDA' W 000° 10.CDB'

If you start at the suggested coordinates you will find the cache a short walk away, the nearest station is Sloane Square, buses stop nearby from there and Clapham Junction.

It is possible for someone in a wheelchair to collect the final but a couple of the stages of the lab could be a problem without assistance, hence the higher D & T ratings here.

BigT & lil'J were first to complete the Adventure 

lisboa_bruno was the FTF the physical cache.

On 04/11/22 I changed the final help in the Lab it seems someone took the hint a little to literally and removed the number.