The idea behind PhotoLoco is that the best way to find out what to visit, or just to see what is generally interesting in a particular place, is to look at what people have photographed and want to share with everybody on the internet.
PhotoLoco does this by enabling you to search through the millions of photos that are available at Flickr and Panoramio, to find photos that were taken within a particular area and match criteria that you specify.
For example, lets say you're in Paris (or are planning a trip to Paris) and want to figure out what would be interesting to see in the museums of Paris. Just enter your current location (or enter Paris as a location), and tell PhotoLoco to search for photos which match museum art.
PhotoLoco will then show previews of all the matching photos it could find at Flickr and Panoramio. You can then select a photo that looks interesting and take a closer look, optionally save it as a favorite for future viewing or maybe see the location on a map and get directions to where the photo was taken, so you can go see for yourself.