St Tudwal's Lighthouse on Saint Tudwal's Island West is active, but unstaffed. The site of the lighthouse, which marks the north end of Cardigan Bay, was purchased by Trinity House in 1876 at the sum of £111 and the next year the stone building was complete. It is 10.7 metres (35 ft) tall, with its focal plane (height of light above high water) at 46 metres (151 ft). The main white light has a range of 14 nautical miles (26 km; 16 mi) and its red sector light has a shorter range of 10 nautical miles (19 km; 12 mi). It gives 1 white and red flash every 15 seconds, the intensity being 12,000 candelas (candle power).