Trwyn Du Lighthouse is a lighthouse between Dinmor Point near Penmon and Ynys Seriol, or Puffin Island, south east Anglesey. It sits at the north entrance to the Menai Strait and marks the passage between the two islands.
There had been a call for a light at this location for some years by master shipmen in the nearby city of Liverpool especially after the steamer the Rothsay Castle ran aground and broke up nearby in 1831 with 130 people losing their lives. The first lighthouse was erected in 1838, at a price of £11,589
The present Lighthouse is 29m tall and was designed by James Walker and built in 1835-1838. It was his first sea-washed tower, and a prototype for his more ambitious tower on the Smalls.
The Lighthouse has a stepped base designed to discourage the huge upsurge of waves that had afflicted earlier lighthouses on the site and reduce the force of the water at the bottom of the tower. The tower is distinguished by its original three black bands painted on a white background.
Walker also pioneered, unsuccessfully, the use of a primitive water closet, comprising a specially designed drain exiting at the base of the tower. The stepped design of the lighthouse may have helped water exit the closet, but surges of seawater made its use difficult during heavy weather.
Dinmor Point is accessible by heading east out of Beaumaris and through Llangoed. For a small fee (£2.50) you can go along a toll road and park very close to the lighthouse or park for free about a mile from the lighthouse. The area around Dinmor contains a cafe, shop and toilets and is good for fishing.
More details of the lighthouse can be found at http://www.penmon.org/page6.htm