Dinas Emrys (Welsh for 'Emrys's city') is a rocky and wooded hillock near Beddgelert in Gwynedd, north-west Wales.

Rising some 76 m (250 ft) above the floor of the Glaslyn river valley, it overlooks the southern end of Llyn Dinas in Snowdonia.

Little remains of the Iron Age hillfort or castle structures that once stood here, save its stone ramparts and the base of a keep [Grid reference SH 60669 49228].

Such remains as are visible today, including three series of ramparts and other walls and some foundations, mostly date to the Middle Ages.

[4] According to legend, when Vortigern fled into Wales to escape the Anglo-Saxon invaders, he chose this lofty hillfort as the site for his royal retreat.

Every day his men would work hard erecting the first of several proposed towers; but the next morning they would return to find the masonry collapsed in a heap.

Vortigern, following the advice of his councillors, was planning to kill the boy in order to appease supernatural powers that prevented him from building a fortress here.

Merlin scorned this advice, and instead explained that the hillfort could not stand due to a hidden pool containing two vermes (dragons).

According to the legend, when Lludd ruled Britain (c.100 BC), a hideous scream, whose origin could not be determined, was heard each May Eve.

A young man who lived near Beddgelert once searched for the treasure, hoping to give himself a good start in life.

Local tradition holds that Vortigern's wise men used to meet here to discuss the great events of their times.

Dinas Ffaraon (Fortress of Pharaoh) or Dinas Ffaraon Dande (Fortress of Fiery Pharaoh) is mentioned in the tale "Lludd and Llefelys" as the place where King Lludd of Britain traps and buries two dragons who are ravaging the land.

[11][12] The name "Dinas Emrys" has been associated with a Roman ruin in Snowdonia, a localization that possibly dates as early as the Historia Brittonum.