SAN FRANCISCO -- Tourism in San Francisco is stronger so far this summer than anytime since the dot-com collapse of 2000 and the Sept. 11, 2001, terrorist attacks, according to the San Francisco Convention & Visitors Bureau.

Business experts say the weak dollar is making the usually expensive region more affordable for Americans, and it's become a downright bargain for foreigners, particularly Europeans and Japanese travelers.

International arrivals at San Francisco's airport are up 4.4 percent so far this year. Luxury hotels in the city's tourist-friendly neighborhoods, such as Union Square and Fisherman's Wharf, are reporting occupancy rates higher than 80 percent.

That's good news for local businesses, who depend on the $7.4 billion that tourism generates each year. Tourism is the single largest source of revenue for San Francisco, and it's a critical element in the economies of surrounding counties, which include the vineyard-filled destinations of Napa and Sonoma counties.