You are looking for a regular sized camouflaged cylindrical container. You do not need to leave the path to retrieve this cache.
Wall Hall is a grand mansion, built in the neo-Gothic style to resemble a castle. There has been a manor house on this site since medieval times but the present hall was built in 1780 and enlarged in the early nineteenth century for George Woodford-Thellusson, a prosperous banker in the City of London. Humphry Repton, a well-known 18th century landscape gardener, designed the surrounding grounds, which includes a Gothic arch folly and an Italian tea garden. In 1910, after a long line of owners, American banker John Pierpont-Morgan Junior bought the mansion. Here he entertained guests including the late Queen Elizabeth, the Queen Mother. During World War II, Wall Hall became the residence of the United States Ambassador, Joseph Kennedy, who stayed here with his family, including his son John F Kennedy, the future US president. It was later used as a hospital for recovering soldiers. In 1942, on Morgan’s death, the mansion and the surrounding estate was gifted to Hertfordshire County Council, to ensure the estate remained forever an area of open countryside to prevent the outward sprawl of north-west London. After the war the mansion was used as a nationally renowned teacher training college and later became part of the University of Hertfordshire. Today the mansion forms a number of privately owned apartments.
... to get to the next cache in the series, continue down into the valley until you arrive at a cross paths with crab lane, just before you reach the footbridge that crosses over a dried up stream, where you can see the river Colne in the distance. Turn left here leaving the Hertfordshire way and head along Crab lane keeping the river to your right, reciting the tongue twister "Red Lorry, Yellow Lorry" as you go. On the way, you will passMoosey's Trail 22 and Moosey's Trail 23.