Colonial architect Mortimer William Lewis designed the Treasury as Sydney's first purpose-built government office. It later housed other government departments before opening as InterContinental Sydney in 1985. The old courtyard was enclosed during the hotel's creation and became its central lounge. A vintage lift remains in operation, while the underground vault survives out of public reach. These details give the building a history that extends beyond its sandstone facade, with former administrative spaces still shaping the way the hotel is used.

Woods Bagot's interior design extends through the guest rooms and public areas, alongside the wellness spaces, Club lounge and dining venues. Greens and blues take their cues from the nearby gardens and harbor. In reception, a feature art wall traces the history of the property and city.

A Classic City Room measures 32 square meters and offers king or twin-double bedding. Its window-side seating and work table allow you to use the room without spending all your time on the bed. Blackout curtains, a coffee machine and Byredo toiletries are among its everyday fittings. The city outlook is the defining feature of this category.

For water and greenery, East Harbour Rooms look over the eastern harbor and Royal Botanic Garden. Harbour Bridge and Opera House Rooms focus on their respective landmarks, while Heritage Rooms face surrounding sandstone buildings. Those names are a more useful guide than a general request for a high floor. The hotel's 32-square-meter Accessible Room has a wheelchair-accessible shower, a shower seat and grab rails at the toilet. Its listed bathroom fittings provide a practical starting point for discussing individual access needs.

The Partial Harbour View Suite increases the space to 70 square meters, with a private bedroom and a separate lounge and work area. There is also a guest powder room, plus a bathroom with a separate shower and bath. King or twin-double bedding is offered. This is a useful step up when a separate sitting room matters more than moving to the most expansive view category.

The upper suites differ in layout as well as outlook. On floor 30, the Royal Opera Suite has a central lounge and separate dining room facing the Opera House and Harbour Bridge. The Presidential Opera Suite is one floor below, with a private outdoor terrace. A lounge, dining room, workspace and master bedroom are joined by a butler's pantry, providing space to arrange a private meal without turning the bedroom into the dining area.

The Treasury occupies the hotel's historic center, where sandstone alcoves and brick arches sit beneath a domed atrium. Its curved central bar and banquette seating create several ways to settle in, from a drink at the counter to a longer lunch. The menu draws on Australian seasonal produce and native ingredients, with botanical cocktails and Australian wines carrying the same theme. Open daily from morning, it is a functioning restaurant and bar within the old building, not simply a place to pass through on arrival.

Weekend high tea brings a more specific Australian character to the table. Finger lime, Davidson plum, wattleseed and lemon myrtle feature in the sweet and savory selection, accompanied by a roaming tea trolley and barista coffee. The Treasury serves it on Saturdays and Sundays from noon to 3 p.m. Reservations and prepayment are required, so this is a scheduled meal rather than an afternoon service available whenever you return.

Breakfast is served at The Conservatory Restaurant on level one, from 6:30 to 10:30 a.m. on weekdays and 7 to 11 a.m. on weekends and public holidays. It gives the morning meal its own venue away from the lobby bar. In-room dining is available around the clock, useful after a late performance or an arrival that falls outside the restaurants' usual service times.

Aster is on level 32, with indoor seating and an outdoor terrace overlooking the Opera House and Harbour Bridge. Native botanicals inform the cocktails, which are served alongside small plates. The bar admits adults aged eighteen and over and requires smart-casual dress; athletic and beachwear are excluded. Reserve a table for a visit here, particularly if it is part of an evening's plans. Minimum-spend conditions apply on specified days, and particular seating requests cannot be accommodated. The bar operates on selected days and does not offer entry solely to look at the harbor.

Club InterContinental uses two floors. Breakfast and morning refreshments are served on level 32, followed by afternoon tea and evening canapes and drinks in the lounge on level 31. Access needs to be included in the booking; a complimentary room-category upgrade does not carry it automatically. Children aged twelve and under are not admitted after 5 p.m., and the dress code is smart casual.

The fifteen-meter heated indoor pool looks toward the Sydney Opera House through tall windows, with reclining chairs beside the water. The gym is also on level 31 and includes rowing equipment, treadmills, cross-trainers, free weights and a Peloton. Regular pool hours run from 5:30 a.m. to 9 p.m., while the gym remains open until 11 p.m. After-hours access is arranged through reception. The pool offers a place for laps without depending on the weather outside.

The hotel's address is 16 Phillip Street, close to the Circular Quay wharves and station. The Opera House, Royal Botanic Garden and The Rocks are all within walking reach, giving a day outside several distinct directions. Ferries extend the route across the harbor, including toward Manly and Taronga Zoo. AirportLink trains connect the domestic and international terminals with Circular Quay, followed by a walk to the hotel. For arrivals by car, the driveway and parking access are on Phillip Street.