Haw Par Villa is recognised for its cultural value and Mount Imbiah Battery for its historical significance, but a lesser-known heritage site has been playing an important role in Singapore for half a century.

The Regional Language Centre (RELC) was set up in 1968 and moved to its present Orange Grove Road site four years later.

In 2016, the 18-storey building was made a heritage site by the National Heritage Board for its part in education - an achievement detailed in a book launched yesterday to mark the centre's half-century.

Celebrating 50 Years Of Excellence As The Regional Language Centre Of Choice was launched at the opening of the RELC's annual international conference.

The RELC is a project of the Southeast Asian Ministers of Education Organisation (Seameo) and provides member countries with training for language educators, language assessments and scholarships. The book tracks the evolution of its courses along with various milestones.

The seminar, which ends tomorrow, is one of the world's longest-running language conferences and is a key forum for professionals and practitioners in language education and research in the region.

Opening the conference was Seameo secretariat director Gatot Priowirjanto, who emphasised the importance of robust language education in South-east Asia, saying: "Strong language skills facilitate better communication to enhance understanding and cooperation among countries and the exchange of information and ideas. These are critical factors for establishing common strategies for the benefit of every country in the region."

Dr Priowirjanto was presented with a copy of the commemorative book by Ms Susan Leong, director of the Seameo RELC Centre.

Also present at the ceremony was Professor Jack Richards, 75, who was honoured for his contributions as an adjunct professor and for introducing a scholarship for one of its master's courses.

Prof Richards, who has been affiliated with the centre since 1973, articulated his hopes for the centre. "Demand for language education is growing so we need to look more at other modes of delivery, such as online and blended learning," he told The Straits Times. "RELC must find out what it can do best within its capacity and bring that to the table within the region."

Edited by Koh Buck Song, Jasminder Kaur and Elsa Yow, the book is on sale at the Seameo RELC library at a promotional price of $50 till March 31. It will cost $70 after that.