The Ventelation Shaft
The ventelation shaft was built just off the centre of the tunnel and was added to allow the smoke from the trains to escape.The shaft is an amazing structure and really needs to be seen to be fully apreciated in all it's glory.
The ventilation shaft is situated approximatley half way along the tunnel but a little closer to the Northampton side.The outer part of the ventilation shaft can be found in a field just outside Great Oxendon on Braybrooke road. It is situated on a bridal path so it is easy to get to and you are able to get very close to it.
The outer part of the ventilation shaft stands approximatley 35 feet high and is aproximatley 15 feet wide from one side to the other.
It can be quite hard to see from the road in the summer time because it is surrounded by bushy trees.