Google City Tours is a Google Labs project that creates tour itineraries using the tried-and-true Google Maps API.

Just type in a starting location (usually a particular city, like Paris or San Diego) and City Tours will automatically generate a multi-day itinerary, walking directions included. Unfortunately, walking directions are the only option; it doesn't provide driving or public transit directions, even though those are supported in other Google Maps applications.

The result is that in some spread-out cities, you'll get directions to walk outrageous distances. For example, when we generated a tour of Ithica, NY, it suggested that we walk 35 miles to only-nearby-by-motor-vehicle Cortland. City Tours is obviously still in an early testing phase, but some features show promise.

You can use it for free right now.