Given the question: The answer to the question: What is the name of the church next to the Old Supreme Court building, the latter of which was also designed by Greenway? is inside the article: One of Greenway's finest works, St James' is listed on the (now defunct) Register of the National Estate. It has been called an "architectural gem" and was featured by Dan Cruickshank in the BBC television series Around the World in 80 Treasures. From 1966 to 1993 the spire of St James' appeared on the Australian Australian ten-dollar note among other Greenway buildings. In 1973, the church appeared on a 50 cent postage stamp, one of four in a series illustrating Australian architecture issued to commemorate the opening of the Sydney Opera House. The Old Supreme Court building, also designed by Greenway with alternations by others, located next to the church is of the same date. Across the square is Greenway's "masterpiece", the UNESCO World Heritage listed-Hyde Park Barracks, designed to align with the church. Beside the barracks stands Sydney's oldest public building, part of the General Hospital built in 1811 and now known as the Mint Building. Separated from the Mint by the present-day Sydney Hospital is Parliament House, Sydney, of which the central section is a further part of the early hospital, and is now home to the New South Wales State Parliament.The church was constructed between 1820 and 1824 with later additions made in 1834 by John Verge who designed the vestries at the eastern end. Apart from these vestries, which retain the established style and proportions, the church externally remains "fine Georgian" much as Greenway conceived it. Relying on the "virtues of simplicity and proportion to achieve his end", Greenway maintained the classical tradition, unaffected by the Revivalist styles that were being promoted in London at the time he arrived in the colony. He planned the church to align with his earlier Hyde Park Barracks, constructed in 1817–19. The two buildings have similar proportions, pilasters and gables and together constitute an important example of town-planning. Before the advent of high-rise buildings, the 46-metre (150 ft) spire used to "serve as a guide for mariners coming up..., can you guess it ?
The answer is:
St James'