Our Prime Meridian Baseball Cap features our iconic 0º 00’ 00” Prime Meridian of the World design that has been printed onto a charcoal grey cap with a golden yellow piping line detail representing the Meridian Line. This cap will provide much-needed shade and protection from the summer sunshine or from an unexpected downpour. This is the perfect souvenir from the home of time.

In 1884 the Prime Meridian was defined by the position of the large 'Transit Circle' telescope in the Observatory’s Meridian Observatory. The transit circle was built by Sir George Biddell Airy, the 7th Astronomer Royal, in 1850. The cross-hairs in the eyepiece of the Transit Circle precisely defined Longitude 0° for the world. As the Earth’s crust is moving very slightly all the time the exact position of the Prime Meridian is now moving very slightly too, but the original reference for the prime meridian of the world remains the Airy Transit Circle in the Royal Observatory, even if the exact location of the line may move to either side of Airy’s meridian.

This Baseball cap is exclusive to Royal Museums Greenwich and is part of our .

Specifications:

• Fully adjustable with a buckle
• Adult size - one size fits all
• Material: 65% Polyester and 35% Cotton
• Washable: hand wash only