what are the blue boxes at the post office
Post box [15] In 1971 the United States Postal Service changed mail collection boxes to the current USPS Dark Blue with contrasting lettering.[12][15][16] The coming of the automobile also influenced U.S. mailbox design, and in the late 1930s, an extension chute or "snorkel" to drive-up curbside collection boxes was adopted.[11]
Post Office Ltd There are currently around 11,500 post office branches across the UK, of which 300 are directly managed by Post Office Ltd (known as Crown offices). The majority of other branches are either run by various franchise partners or local subpostmaster or operators (who may be members of the National Federation of SubPostmasters or the CWU Postmasters Branch), as "sub-postoffices".