trawling industry expanded and by 1933 Aberdeen was Scotland's top fishing port, employing nearly 3,000 men with 300 vessels sailing from its harbour. By the time oil was coming on stream, much of the trawling fleet had relocated to Peterhead. Geologists had speculated about the existence of oil and gas in the North Sea since the middle of the 20th century, but tapping its deep and inhospitable waters was another story. With the Middle Eastern oil sheiks becoming more aware of the political and economic power of their oil reserves and government threats of rationing, the industry began to consider the North Sea as a viable source of oil. Exploration commenced in the 1960s and the first major find in the British sector was in November 1970 in the Forties field, east of Aberdeen. By late 1975, after years of intense construction, the necessary infrastructure was in place. Oil flowed through the Forties pipeline system directly to the refinery at far-away Grangemouth. Business In 2011, the Centre for Cities named Aberdeen as the best placed city for growth in Britain, as the country looked to emerge from the recent economic downturn. With energy still providing the backbone of the local economy, recent years have seen very large new investment in the North Sea owing to rising oil prices and favourable government tax incentives. This has led to several oil majors and independents building new global offices in the city. Five of Scotland's top ten businesses are based in Aberdeen with a collective turnover of £14 billion, yielding a profit in excess of £2.4 billion. Alongside this 29 of Scotland's top 100 businesses are located in Aberdeen with an employment rate of 77.9%, making it the second highest UK city for employment. Figures released in 2016 ranked Aberdeen as having the second highest number of patents processed per person in the UK. Shopping The traditional shopping streets are Union Street and George Street, now complemented by shopping centres, including the Bon Accord Centre and the Trinity Shopping Centre. A £190 million retail development, Union Square, reached completion in late September/early October 2009. Major retail parks away from the city centre include the Berryden Retail Park, the Kittybrewster Retail Park and the Beach Boulevard Retail Park. Aberdeen Market has been rebuilt twice, but closed in 2020. In March 2004, Aberdeen was awarded Fairtrade City status by the Fairtrade Foundation. Landmarks Aberdeen's architecture