Two Slots

Most of the old town of Bradford-on-Avon is built into a steep valley. It's even hazardous standing to post a letter. Fortunately few people post letters these days.
The 'ROYAL MAIL' legend first appeared on letter boxes in the early 1990s; prior to this letter boxes had the words 'POST OFFICE' cast onto them. The change was prompted by the separation of Post Office Counters Limited and Royal Mail as independent companies.