1 Whitehead Street
You won't find many shells on the beaches of Key West, due to the reef that also keeps the heavy waves farther out to sea. But, if you are a shell "freak" like me, a trip to the Shell Warehouse will more than help you get your fix. The shop is right near Mallory Square in the middle of the most tourist-y area and not in any way authentic to Key West. But, I have to include it here as a recommended stop because shells are awesome and the Shell Warehouse has some awesome shells.