The parish church of St Deiniol is a grade II* listed building. 
Caer gai, a Roman fort near Llanuwchllyn, was traditionally known as the home of Sir Kay, the character in the Arthurian legend. Poets of the 15th century recorded a story, ultimately deriving from the Prose Merlin included in the Lancelot-Grail and the Post-Vulgate Cycle, that King Arthur and Sir Kay were brought up at Caer-gai as foster brothers. Caer gai is also grade II* listed. 
- Llanuwchllyn Census 2001 National Office of Statistics
- "Parish Church of St Deiniol, Llanuwchllyn". British Listed Buildings. http://www.britishlistedbuildings.co.uk/wa-24688-parish-church-of-st-deiniol-llanuwchllyn. Retrieved 17 December 2013.
- Bromwich, p. 311.
- "Caer Gai, including adjoining forecourt walls to the NE, Llanuwchllyn". British Listed Buildings. http://www.britishlistedbuildings.co.uk/wa-4683-caer-gai-including-adjoining-forecourt-wal. Retrieved 17 December 2013.
- Rachel Bromwich (2006). Trioedd Ynys Prydein: The Triads of the Island of Britain. University Of Wales Press. ISBN 0-7083-1386-8.