Royal Observatory Greenwich

SG Flamstead House, 1676, 1st

SG Airy Transit Circle Telescope, 1st

SG Shepherd Gate Clock, 1852, 1st

SG Prime Meridian, 1884, 1st

SG Great Equatorial Telescope, 1893, 1st

SG Annie Maunder Astrographic Telescope, 2018, 1st

SG H1, c.1735, 1st

SG H2, c.1739, 1st

SG H3, c.1759, 1st

SG H4, c.1759, 1st

First Day of Issue Official Covers