the mouth of the River Ythan and westward to the Powk Burn. In 1894, the Peterhead Harbours Act was passed, the various objects of which included the building of a fish market and to acquire a short line of railway. 20th and 21st centuries South Harbour was deepened between 1906 and 1908. The Harbour of Refuge (Admiralty Backwaters) was begun in 1886 by Sir John Coode. It was built by convict labour. The present harbour, now a Category B listed structure, has two massive breakwaters, enclosing an area of approximately in Peterhead Bay. The south breakwater, about long, was constructed in 1892–1912 using convict labour from the prison. Peterhead was, and remains, an important fishing port, and the breakwater gave it an advantage over other fishing ports. The north breakwater, constructed 1912–1956, is approximately long. Peterhead was a Jacobite-supporting town in the Jacobite risings of 1715 and 1745. In particular, it was one of the Episcopalian north-eastern ports where reinforcements, plus money and equipment, were periodically landed from France during the Forty-Five. A new phase of growth was initiated in the 1970s with Peterhead becoming a major oil industry service centre, and the completion of the nearby St Fergus gas terminal. At this time, considerable land holdings were allocated for industrial development. From the 1990s onward, the town has suffered from several high-profile company closures and is facing a number of pressures, including Common Fisheries Policy reforms. However, it retains a relatively diverse economy, including food processing, textiles, service industries and, still importantly, fishing. (Over 163,000 tonnes of fish and shellfish, with a value of around £179m, were landed at Peterhead in 2017, employing around 700 fishermen.) The Peterhead Port Authority plans to extend the northern breakwater as a stimulus to the town's economic development. In addition, to assist with business diversification and town centre environmental improvements, the 'Peterhead Project' initiative under the Aberdeenshire Towns Partnership brings together the Council, Scottish Enterprise Grampian, Communities Scotland, commerce and community representatives. The town's port remains the largest for landings in the United Kingdom. According to a 2019 UK sea fisheries statistical survey, Peterhead Port's catch size for the year was 132,000 tonnes. Nearby Fraserburgh was third, behind Lerwick. It was placed 14th in the list of number of fishers based at each port. Listed buildings Peterhead has many listed buildings across the three categories of A, B and C. The three Category