Llandilo Avenue was developed in two stages. The section between Cotswold Rd and Kingsland Rd was formerly called Blanche Street. After the 1910 subdivision of the ‘Llandilo’, the home of Sir Phillip Sydney Jones (now Trinity Grammar Preparatory School), a road was created. This road was added to Blanche St and the street was renamed Llandilo Avenue. ‘Llandilo’ is the birthplace in Wales, of Jones’ father.