Siblings Hajah Maimunah Shaik Madar, 84, and Haji Ansari Shaik Madar, 79, have fond memories of a childhood spent inside the grounds of the Istana.
They are not the children of the Straits Settlements governors and Singapore presidents who lived or worked there.
Nor are they related to the countless foreign dignitaries ushered through the gates since the late 19th century.
Their father was a Turkish immigrant who had a job as chief orderly at what was then known as the Government House. From the early 1930s to late 1940s, he and his family of 13 children lived on the grounds in a bungalow, which has since been demolished.
Brother and sister paint an idyllic picture of their days on the spacious, leafy grounds of what is now the official residence and office of the President of Singapore - plucking fruit from the mangosteen, butterfruit and mango trees as they pleased, feeding horses in the stables, and playing rounders with the children of other staff.
Mr Ansari, a retired bank officer, recalls the ceremonial pomp associated with the Government House. He added: "It was a very grand building on elevated ground. Impressive - really like a palace."
Both the Istana ("palace" in Malay) and Sri Temasek bungalow were completed in 1869. In 1992, they were gazetted as national monuments. The Istana was intended as the residence for the governor of the Straits Settlements.
The undulating, leafy grounds were bordered by Orchard Road to the south, Cavenagh Road to the west, Bukit Timah Road to the north and Mount Sophia to the east. The main building is on elevated land and was constructed facing the sea, making it open to prevailing winds.
Madam Maimunah recalls that access to the main Government House building was restricted, although the doors would sometimes be flung open for movie screenings for staff and their children. Once, she confesses, she sneaked up onto the roof where the flagpole was.
Government House's construction was initiated by Sir Harry St George Ord, the first governor of the Straits Settlements. He acquired 43ha of land from C. R. Prinsep's diseased nutmeg plantation in 1867.
Ord reassured the Legislative Council that extravagance would be avoided. But by the time Government House was completed, the cost had grown to over 185,000 Spanish dollars - nearly twice the original estimated budget.
Thousands of Indian convicts were roped in. While this was done to reduce costs, the convicts also brought with them technical expertise lacked by the local coolies, who were unskilled in classical designs.
The colonial engineer, Major John F. A. McNair, who was the architect of Government House, incorporated European and Malay elements into its architecture.
Neo-Palladian influences are evident - Doric, Ionic and Corinthian pilasters and columns are found on the first, second and third levels respectively. Characteristics typical of Malay houses improved ventilation in the tropical heat: wide verandahs, large louvred windows, and dwarfed piers and arches elevating the entire structure.
The main building's front facade is dominated by an imposing projected portico, flanked by twin porticoes crowned with triangular pediments. The bulk of building materials came from the region: stone and granite from Pulau Ubin, lime from coral atolls around the island, and marble from neighbouring countries like Java. The timber was felled on Singapore soil, and internal walls were plastered with Madras chunam, a form of stucco.
Government House was not praised for its architectural merits initially. And its interiors, academic K. K. Seet wrote in The Istana (2000), supposedly paled in comparison to the homes of rich Chinese merchants at the time.
Nonetheless, it became known as a hub of hospitality for foreign dignitaries. Its architecture earned praise from British royalty, including the future King George V who visited in 1882. An 1890 guidebook to Singapore called it "the finest building of its kind in the Far East".
Sri Temasek, a double-storey bungalow on the Istana grounds, was once the colonial secretary's residence. It has spacious verandahs on its ground floor and is a mix of European and Indian elements. It was designated as the official residence of the prime minister after Singapore gained independence.
During World War II, the Japanese military seized control of the Istana. In 1943, the Japanese Supreme Commander Count Hisaichi Terauchi made it the General Headquarters of the Southern Expeditionary Forces - relocating it from Vietnam.
Domestic staff who survived the bombings were brought back to work for Terauchi, who reportedly treated them well. The Japanese left the Government House intact, aside from redecorating a few rooms in Japanese style and destroying items that bore the British crest.
Madam Maimunah, a retired Malay teacher, said: "In other places, the Japanese were rough. But in the Istana, they were more disciplined... One officer told me I was like his daughter, and he gave me Japanese snacks."
British and Australian prisoners of war had to bury dead Japanese soldiers near Government House, and repair the basement and parts of fences that had been damaged by shells.
SPECIAL CARE DURING WWII
In other places, the Japanese were rough. But in the Istana, they were more disciplined... One officer told me I was like his daughter, and he gave me Japanese snacks.
MADAM MAIMUNAH SHAIK MADAR, who spent her childhood on the grounds of the Istana.
Food shortages meant that Government House's golf course ended up as fertile ground for crops such as banana, tapioca, yam and tomato. The residents, who also reared chickens, would sell these vegetables in the market.
After the war, the last British governor, Sir William Goode, served for six months before handing over the office to Singapore's first president Yusof Ishak in 1959, when Singapore attained full self-governance.
Government House was renamed Istana Negara Singapura (Palace of the State of Singapore). This was shortened to The Istana after Singapore separated from Malaysia in 1965.
In a place buffeted by the waves of history, it is hardly surprising that some of its cultural artefacts have gone missing over the years.
Two significant recoveries were made in the 1990s: a statue of Queen Victoria and a 46cm statue nicknamed the Guardian of the House, which convict labourers worshipped as a spiritual benefactor and now rests on the grand staircase of the main building.
Today, local officials are introduced to visiting heads of state and ministers in the Reception Hall. Foreign guests are hosted to state banquets in the Banquet Hall, and official ceremonies, such as the swearing-in of ministers and national award investitures, are sometimes held in the State Room.
The Istana grounds are open to the public several times a year on certain public holidays. Current president Halimah Yacob plans to open them to the public more often. "I want to see the Istana becoming more accessible to ordinary Singaporeans," she said.