File:Pole Hill, Chingford, London E4 - geograph.org.uk - 1053652.jpg

English: Pole Hill, Chingford, London E4. Pole Hill stands in Epping Forest at 0 degrees longitude, and 51 degrees 38 minutes latitude. At its highest point it is 91 metres above sea level. It is chiefly noted for the fact that it lies directly on the Greenwich meridian and, being the highest point on that bearing directly visible from Greenwich, was at one time used as a marker by geographers at the observatory there to set their telescopes and observation equipment to a true zero degree bearing.

On top of the hill there are two obelisks. The larger is made of granite and bears the following inscription:

This pillar 1053632 was erected in 1824 under the direction of the Reverend John Pond, MA, Astronomer Royal. It was placed on the Greenwich Meridian and its purpose was to indicate the direction of true north from the transit telescope of the Royal Observatory. The Greenwich Meridian was changed in 1850 and adopted by international agreement in 1884 as the line of zero longitude passes 19 feet to the east of this pillar.

At that point (19 feet / 5.8m east) there is a smaller concrete obelisk, which marks the true modern position of the Greenwich Meridian. The pillar however was not erected to mark the meridian. It is an Ordnance Survey trig point 1053624 placed here to mark the top of the hill. The fact that it is on or near the Meridian is a coincidence.

I have also been told by a friend who lives near Pole Hill that when the weather conditions are right it is possible to see the Laser at Greenwich marking the Greenwich Meridian.