SINGAPORE - The Merlion, Changi Airport's Control Tower and the Botanic Gardens have topped a list of 53 buildings, sites and structures in a study on Singapore's built heritage.

Some 1,500 people surveyed by the Institute of Policy Studies (IPS) ranked the trio as "most important to them".

IPS senior research fellow Natalie Pang said the trio of landmarks have, over time, become iconic, international symbols associated with the country.

For instance, the Merlion likely emerged on top because of its prominent role in branding Singapore as a tourist destination, its promotion of a unique Singaporean identity, and its symbolism of a nation eager for economic success, she said.

This is despite the low likelihood of Singaporeans visiting the attraction, which is located near the Fullerton Hotel, regularly, she added.

The two-year study, the first of its kind, sought to establish a framework as to how Singaporeans appraise the country's built heritage. IPS surveyed Singaporeans aged 18 to 70.

According to the study, older respondents aged 49 to 70 who perceived colonial buildings such as the former Supreme Court as important - as well as those who liked the physical appearance of infrastructure such as Changi Airport's Control Tower, the Benjamin Sheares Bridge, Clifford Pier, and Tanjong Pagar Railway Station - were more likely to have a strong sense of national identity.

This appeal was in turn linked to a strong sense of national identity.

However, this link was not as apparent among younger respondents.

IPS said the study, which was supported by the National Heritage Board's Heritage Research Grant, reveals the diversity in public perceptions of heritage.

It believes the findings can help heritage bodies adjust promotional programmes and policies.

It pointed out that dominant discourses on built heritage have largely taken place among professionals such as academics, policymakers, heritage-related practitioners and activists.