The architect behind this staggering edifice was Leandro V. Locsin, a Filipino from Silay in Negros Occidental who had studied pre-law, then music, before finally turning to architecture. Locsin was a talented pianist and a grandson of the first governor of his province -- an unconventional path to designing the world's largest home. By the time Sultan Hassanal Bolkiah commissioned him, Locsin had already designed the Philippine Pavilion at the 1970 World Expo in Osaka and the Church of the Holy Sacrifice in Manila, known for its pioneering thin-shell concrete dome. For Brunei, Locsin drew on Islamic and Malay architectural traditions, translating them into golden domes and sweeping vaulted roofs that echo mosque design at residential scale. The interior was handled by Dale Keller Interior Designers, while construction fell to a multinational effort: Ayala Abbott and Butters from the United Kingdom and Hagen International from Denmark, with ten thousand workers drawn from seventeen countries.

The statistics resist comprehension. Beyond the 1,788 rooms and 257 bathrooms, Istana Nurul Iman houses a banquet hall that can expand to seat 5,000 guests, a mosque accommodating 1,500 worshippers, a 110-car garage, five swimming pools, and air-conditioned stables for the sultan's 200 polo ponies. The total floor area -- 2,152,782 square feet -- exceeds that of any other residence on Earth. Completed in 1984, the year Brunei gained full independence from Britain, the palace became both the sultan's home and the seat of government. Its position on the banks of the Brunei River places it within sight of the capital but set apart from it, screened by tropical vegetation on its sprawl of riverside hills. The palace replaced Istana Darul Hana, the modest hilltop compound where Hassanal Bolkiah's father had governed for three decades.

For most of the year, Istana Nurul Iman is closed to the public. Its gates open only during Eid al-Fitr, the festival marking the end of Ramadan, when approximately 110,000 visitors pass through over three days. The sultan and his family receive guests personally. Visitors are given gifts of food, and young children receive green packets containing money -- a tradition of royal generosity that transforms the world's most exclusive address into something briefly, remarkably communal. During the ten days of the Ramadan period, the palace also opens to Muslims for Tadarus and Tarawih prayer gatherings. These annual openings offer the only public glimpse of an interior that few outsiders have ever described in detail, a space where Locsin's architectural vision meets the accumulated wealth of one of the world's last absolute monarchies.

Istana Nurul Iman is inseparable from the story of Brunei's oil wealth. The sultanate's offshore petroleum reserves, first discovered in 1929, generated the revenue that made a $1.4 billion palace conceivable. The timing of its completion in 1984 -- the same year Brunei achieved full independence -- was no coincidence. The palace was a declaration: a small nation of a few hundred thousand people, wedged between the Malaysian states of Sarawak and Sabah on the northern coast of Borneo, could build the largest home on the planet. Whether that declaration reads as triumph or excess depends on the observer. What is beyond dispute is the building's physical reality -- the golden domes rising above the Brunei River, the vaulted roofs designed by a pianist-turned-architect, the stables cooled by the same air conditioning that chills the banquet hall. It is a palace that refuses to be subtle, and Brunei has never apologized for it.