Threemilestone currently has 6 mapped postboxes recorded by The Postbox Hunter. The postboxes in Threemilestone include 2 recorded royal cyphers. The most common is EIIR, recorded on 5 postboxes, representing 83.3% of the mapped total. The complete recorded cypher list is: EIIR (5) and crown (1). The most commonly recorded postbox type is Pillar, with 3 mapped examples. The data contains 3 different recorded postbox types. Across the available tagging data, 2 designs are represented. This information is generated from the latest postbox location and tagging data available to The Postbox Hunter.