Van Kleef Aquarium was an oceanarium located along River Valley Road, at the foot of Fort Canning Hill, in Singapore.

Construction subsequently began in 1940, but work was halted after piling was completed due to rising material costs, only resuming in 1952 on a new site.

The aquarium opened in September 1955, after multiple delays and with part of the costs borne by the City Council of Singapore, and had 150,000 visitors in its first three months of operation.

[5] In 1933, the committee recommended spending the money on either of two projects, the conversion of the old race course into playing fields and the construction of an aquarium.

Construction of the Van Kleef Aquarium commenced in 1952,[17] with half of the costs borne by the City Council and on a new site.

[25] After its opening, the aquarium performed above the City Council's expectations, receiving 150,000 visitors and raking in $40,000 in revenue in it first three months of operation.

[27] The aquarium started selling sea water to marine fish enthusiasts in 1967, and remained largely popular with locals and foreigners in the 1970s.

[25] The upper level comprised several dimly lit rooms ringed by the aquarium tanks, as well as offices and an inquiry counter.

Embellished with sand, rocks and corals, the tanks were connected to service passages to facilitate the maintenance and upkeep of them as well as their inhabitants.