During Victoria times a number of postal franking marks were introduced which consisted of an oval containing a number which indicated the Office. The stamp on the right is an early penny brown imperforate stamp carrying the number 810 - for Tring. The web site GBStamps.co.uk has a useful list of all the Early English Post Office Numbers - which includes the following Hertfordshire numbers.
.It is planned to add additional examples to this page
|513||Market Street (Markyate)|
|D44||Potters Bar (Middlesex)|
|July 2012||Page Created|
|July 2013||Berkhamsted added|