Photo by M.V. Jantzen

Maybe letting them stand on the left side of the escalator is worth it after all.

Destination D.C., the city’s tourism agency, reported yesterday that close to 18 million visitors came to our fair city in 2011, the highest number since the September 11, 2001 attacks. Of those, the overwhelming majority—16.1 million—were domestic tourists.

All those visitors bring with them a lot of cash to spend locally—$6 billion, all told, a 6.2 percent jump from 2010 levels. The spending emboldened the city’s hospitality industry, adding 11,500 jobs for a total of 76,000 people employed at local hotels, restaurants, bars, tour companies, etc. After the federal government, the hospitality industry is second-biggest employer in D.C.

Though international tourists account for a small proportion of all visits, they tend to spend more than their domestic counterparts. In 2009, for example, international tourists represented only 10 percent of all visitors but accounted for more than 20 percent of all the spending. In 2010, Washington ranked seventh in the country in international visits, and its biggest feeder markets were the United Kingdom, Germany, Australia, China, France, India, Japan, the Benelux countries, Brazil and Italy.