In the Harley Quin short story The Sign in the Sky, Deering Vale is a village in which Deering Hill, the residence of Sir George Barnaby is located. It is located nineteen miles from London with a rail connection, making it suitable for example for people such as Sir George who commutes to London daily.
The exact location of the village is not stated but trains for Deering Vale depart from London Waterloo, suggesting that it is located southwest of London in Surrey. According to Mr Satterthwaite there is only one train per hour to and from London. The train departs from London at 48 minutes past each hour and takes about 40 minutes.