At the top and now the downward stretch

Here is a picture of the top of the Marsworth Flight.
Hallmark is just leaving the Top Lock at Bulbourne Junction.
The main Grand Union is going down to London.
But first Hallmark has to cruise through the impressive Tring Cutting which is about three miles long and up to 30 foot deep in places.
This gets the canal over and through the final part of the Chilterns.
Brentword here we come!