We did not find the website of terribly helpful whereas is far more informative and with reference to the GLO says: "Charles II appointed Henry Bishop as the first Postmaster General who established the General Letter Office. All the post went to London, where clerks calculated the charge to be paid by the recipient".
This section lists the memorials where the subject on this page is commemorated:
General Letter Office
Commemorated ati
General Letter Office
Near this spot the General Letter Office stood in Post House Yard, 1653 - 166...
Other Subjects
Jamrach's Emporium
Exotic shop dealing in wild animals. It was run by Charles Jamrach, who inherited the business from his father. Known to seafarers throughout the world, they would bring animals from distant lands ...
2 memorials
1 memorial
1 memorial
Madame Tussaud
Born in Strasbourg as Marie Grosholtz. Her mother worked for Dr Curtius, a wax modeller, who taught his skills to Marie. In the French revolution made death masks of the executed nobles and royalty...
2 memorials
Whitecross Street Market
One of London's oldest markets.  Started trading in 17th century and was known locally as "Squalors Market".  This information, on the plaque, comes from Wikipedia.  We can't add to it.
1 memorial
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