The historic Central School site in Hollywood Road was opened yesterday for public visits as the government kicked off a three-month public consultation to decide its future.
More than 600 people, including representatives of more than 20 non-governmental organisations, enrolled for the first tour, which will close at 6pm today.
Redevelopment of the married police quarters was put on hold after archaeologists uncovered remnants of the school, where many of Hong Kong's best-known figures were educated.
Sun Yat-sen, regarded as the father of modern China, attended the school at its earlier site in Gough Street before it moved to Hollywood Road in 1889.
Archaeological investigation unearthed more than one-third of the former Central School's foundations, along with broken pieces of porcelain utensils and ceramic tiles, made both locally and overseas.
Part of the foundations had been disturbed by the construction of the police quarters on top of them in 1948.