Hey! You a Tourist or Sumpin'?

Ray Rosato speaks a mile a minute and doesn't much care if anyone understands a word. As he sees it, inflicting his thick Noo Yawk accent on a clutch of bewildered tourists, blared through a tinny microphone as his double-decker bus trundles through the streets of lower Manhattan, is half the fun of his tour.

Sounding like a mafioso wanna-be, he recounts the history of his beloved burg. "So how did New Amsterdam become Noo Yawk City? Well, basically, the British sailed into da harbor and told Peter Stuyvesant- -he was dis Dutch guy--to fuggedaboutit. And Stuyvesant said, 'I'm outtaheah,' and that was how the British got Noo Yawk from da Dutch."

The sightseeing season is upon us. You can always tell because the magnolias bloom at the botanical garden and the sidewalks sprout meandering, camera-toting fatties from the Midwest. To get a tourist's- eye view of how our city presents itself, I'd hopped on Rosato's bus. My motive was not mere curiosity. The city recently announced that all its 1,300 tour guides must be retested if they want to retain their licenses. And believe it or not, Rosato is considered one of New York's good guides.

Now, I know that tour guides often have an unsavory reputation. But is testing them really necessary? Maybe in Turkey, I thought. Visiting there once, a would-be guide accosted me at the bus station and offered to be my personal escort. He ended up taking me only to his uncle's carpet store, where I was expected to be fleeced. That wouldn't happen in New York, of course. Here it's the uncle's delicatessen, not a carpet store. But hey, there are plenty of guides who will blithely tell tourists that Central Park is the city's largest. It ain't.

"A bad tour guide can ruin your trip," says the city's Consumer Affairs commissioner, Gretchen Dykstra. To protect visiting ...