The Session Hut was built just near Lake Birrell, about 400 metres south of the fire trail junction at Medlow Gap.
The corrugated iron hut is in disrepair and showing its age. It was probably built somewhere between 1944 and 1963.
The Session Hut could have been used for shelter in an emergency. I heard it has been demolished.
Unfortunately the Water in Lake Birrell is not suitable for drinking.
Blue Mountains National Park (NSW)