Peedie is the Orkney word for small so this small area of water is called the 'Peedie Sea'.

The Peedie Sea was formed when a shingle bank known as a 'Ayre' was formed in front of a small bay. The ayre now has the Ayre Road running along the top of it. The Peedie Sea used to be a fair bit bigger but it was filled in on its east side and large parts of Kirkwall built on it. It used to reach to nearly in front of St. Magnus Cathedral. In viking times the Cathedral was built on the solid ground nearest to the shore to make getting the stone to the site as simple as possible.