There is no shortage of iPhone/touch apps that allow you to use the navigation capabilities of your device to figure out where you are or where you need to go. Google Maps, already built in, does a great job all by itself.
Increasingly, there are many paid and free apps that can do the job in a simpler, more specialized, or more efficient way. One of the highly praised and heavily downloaded apps is AroundMe, which can show you nearby restaurants, hotels, theaters, parking, hospitals and much more.
If you have GPS, or wi-fi location ability activated, AroundMe will take it from there. Click on a category, and you'll get a list of destinations arranged by distance. Click on a destination, and you can get an address, the distance, a link to Google Maps to show you the route, a button to add the destination to contacts, and if there is one, an email address for the place you're headed.
There is also a category of searches called 'nearby' that can identify nearby cities, parks, geographical locations, airports and attractions. Those destinations link to appropriate Wikipedia entries. Cool.
All in all this is a terrific, free app. While it has many competitors, some free, some paid, I think this is a very powerful way to use your iPhone when you are on a trip, or even in your home town to locate things you might never have known were there.
AroundMe is localized in English, French, German, Portuguese, Swedish and Japanese.
Things that would be nice to add would be some form of filtering, such as type of cuisine rather than just restaurants, or animal hospitals instead of all hospitals.
I use AroundMe several times a week because like all good apps, 'it just works'.