St Mary’s Cathedral is the seat of the Roman Catholic archbishop of Sydney (currently the controversial Cardinal George Pell) and stands on the site of Australia’s first Catholic chapel. William Wilkinson Wardell’s design replaced the original cathedral, ruined by fire in 1865. Constructed from local sandstone, it’s the largest Gothic cathedral in the southern hemisphere – 106m (348ft) long with a 46m (150ft) central tower – dwarfing many of the European models from which it took inspiration. Wardell’s original twin spires, initially not erected due to funding problems, were lowered into place by helicopter in 1999. Don’t miss the cathedral’s crypt, which is decorated with a beautifully designed terrazzo floor depicting the six days of Creation.