If you walk the Wall at any time between the beginning of May and the end of October you can collect a series of stamps on a folded card as evidence of completing the whole trail. This is called the Hadrian's Wall Passport. Collect the full set of stamps and you are entitled to purchase a commemorative badge and certificate from the two end points of the trail.
As well as providing walkers with a souvenir it encourages those doing the trail to follow it at the time of year when the least erosion damage might occur. When we were planning the route we were unaware of this and so walked it just before the beginning of May!!! The stamping stations are:
Segedunum Roman Fort : Robin Hood Inn : Chesters Roman Fort : Housesteads Fort : Birdoswald Roman Fort : Sands Sports Centre Carlisle ( by the Eden Bridge ) and either The Banks Promenade or The King's Arms in Bowness

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