Prime Meridian of the World

We're here! The astronomers have arrived at 0 degrees longitude - the prime meridian. From this spot is calculated the longitude of everywhere else in the world.

In the photo the girls have a foot in both camps, east and west :)

Also from here early astronomers worked out the position of many stars we can see in the night sky, designated by right ascension and declination (RA and Dec) - the equivalent of latitude and longitude on earth.

Tonight we're celebrating our fab visit by going to Nando's. Guess who chose the venue? :)