Altazamuth Stone

Knightstown’s Place in the History of Cartography

There was a time when there were no lines of longitude. Briefly, without lines of longitude ships, were lost when out of sight of land. Yes, the stars and skies were a great help, but when there was cloud coverage for long periods, ships were ‘lost’.

Where does Knightstown, Valentia Island come into all this?

In 1844, an experiment took place from Valentia Island actually measuring distance physically in conjunction with time to Greenwich in England. This marked out the lines of Longitude. Then in 1862, because Valentia Island was connected by telegraph to the mainland, a different experiment took place to confirm the readings from 1844. Both figures were conclusive and exact. The second experiment used an instrument called an Altazamuth (the actual instrument is housed at the observatory in Greenwich). To mark the spot where the 1862 experiment took place, a stone was laid in Jane Street, Knightstown. While the original stone was and is battered by the weather, the Knightstown Tidy Towns group made a replica and placed it close to the original spot for all to see.

The Altazamuth walk begins at the Altazamuth Stone on Jane Street and leads you up to Cracow Park & Playground or down to the seafront adjacent to the Church of the Immaculate Conception. The walk itself is edged by wildlife habitats and gardens, it features a bench halfway for taking a moment and forgetting the troubles of the world, pure heaven!