Perth Cathedral was built by the London architect, William Butterfield and is an A listed building. In the year he designed St Ninians he also designed Adelaide Cathedral in Australia and Fredericton in Canada. The Butterfield design was completed in two phases in 1850 and 1890. Another London architect, John L Pearson designed the Lady Chapel and the Chapter House around 1900; these additions were carried out by his son, Frank Pearson. Episcopal churches are usually aligned east to west that the morning sun rises and shines through the window above the altar. Above the altar at the cathedral there is a beautiful baldacchino designed by Pearson. In the middle ages important people moving around had an escort of four men holding poles upright with a silk cover stretched between them to protect them from the sun. The Doge of Venice is usually pictured under one of these. This feature over the altar is similar and is called a baldacchino.