More people are visiting whisky distilleries than ever before, spending tens of millions of pounds as they come to see how Scotland's celebrated spirit is made.

A new survey by the Scotch Whisky Association (SWA), carried out for the 'Whisky month of May' in this Scotland's Year of Food and Drink, reveals that more than 1.5m people were attracted to distillery visitor centres across the country in 2014, up around 6 per cent on the previous year. This represented an increase of more than 15 per cent from just under 1.3m in 2010.

According to the SWA , in terms of visitor numbers it means that Scotland's distilleries collectively, are among some of the best-known UK attractions, including Edinburgh Castle, the Scottish National Gallery, Tate Britain, Stonehenge and London Zoo.

The largest proportion of visitors came from Scotland and other parts of the UK, Germany, USA and France, reflecting some of the largest markets for Scotch whisky. The USA is the biggest market by value, followed by France and Germany ranks at number five.

Visitors to distilleries spent a total of almost £50 million last year on tours and in their shops and cafes, up from £27m in 2010. The average spend per visitor last year was around £32.50. The increase in spend in recent years reflects investment by producers to enhance their visitor centres and to provide a wider range of offerings, such as special bottlings, tailored tasting and blending sessions.

Julie Hesketh-Laird, Scotch Whisky Association deputy chief executive, said: "Our survey shows just how many people want to visit distilleries to see how Scotch Whisky is made, try a dram and buy a bottle to take home to family and friends. Every year, distilleries are attracting more visitors from the UK and all parts of the globe.

"Scotch Whisky producers are investing in their centres and shops to give visitors the best possible experience. As well as providing another source of income for producers, the increasing number of visitors is good for the wider Scottish economy. Visitors are spending more at distilleries and are likely to being doing the same with other businesses, including hotels and restaurants. It also helps put Scotland on the map."

Mike Cantlay, VisitScotland chairman, said: "Research shows time and time again how popular distilleries are with visitors and with five distinct whisky regions, each producing their own unique characteristics and flavours, every visit offers a different taste of the county's important whisky tourism industry."

Scott Fraser, Tomatin Distillery visitor centre manager near Inverness, said: "Our visitor numbers are increasing, as is the amount people spend when they come to see us. We've completely revived our tour offering and the feedback has been brilliant, both from private tourists and an increasing number of coach tour business. The brand has been performing well in the UK and in our export markets and this has had a direct impact on our visitor numbers. ."

Mickey Heads, Ardbeg Distillery manager on Islay said: "Distilleries like Ardbeg have become a place of pilgrimage for the Single Malt Whisky faithful and these findings echo the growth in visitor figures we have experienced. We pride ourselves on being one of the island's fastest growing distilleries.

"We firmly believe Ardbeg encapsulates all that Islay has to offer, in all its raw natural beauty. This year marks Ardbeg's 200th Anniversary and we look forward to sharing the true spirit of this whisky with many more visitors and raising a dram to the next 200 years."