Wall boxes are a type of post box or letter box found in many countries including France, the United Kingdom, the Commonwealth of Nations, Crown dependencies and Ireland. They differ from pillar boxes in that, instead of being a free-standing structure, they are generally set into a wall (hence the name) or supported on a free-standing pole, girder or other stable structure. In the UK, UK Dependent Territories, Colonies and former Colonies and in many former British Empire countries, wall boxes usually bear the initials of the reigning monarch at the time the box was made. The first UK wall boxes were erected in 1857 in Shrewsbury and Market Drayton.