Anglesey who could speak Welsh are as follows: Today, Welsh is less widely used on the island, but it is still the dominant language in certain areas, particularly in the centre, including the town of Llangefni, and some areas of the south coast. A notable example is the village of Llanfairpwll. The island's five secondary schools vary widely in the percentage of their pupils who come from predominantly Welsh-speaking homes, as do the percentages who can speak Welsh: The geology of Anglesey is notably complex and is frequently used for geology field trips by schools and colleges. Younger strata in Anglesey
Holyhead Mountain Bodafon Mountain () on the main island. On the east side of the mountain is the site of a late Roman watchtower called "Caer y Tŵr" (Tower Fortress), from which Holyhead Mountain's Welsh name is derived. Holyhead Mountain also has an Iron Age stone circle settlement near its foot. This shows evidence of being occupied in the middle part of the Stone Age, the Neolithic Age, the Bronze Age and the Iron Age. There are traces of field systems and the bases of dry-stone walls of twenty huts, and there are a number of standing stones in the vicinity. The