The Principality of Monaco is the second-smallest country in the world – behind Vatican City!  The country is in the French Riviera, along the Mediterranean Sea.  I popped over to Monaco for a day while spending a long weekend in Nice, France.  Monaco is a very quick (and scenic) train-ride from Nice.   Most people associate Monaco with the Monte Carlo Casino and the Grand Prix, but the destination has a lot more to offer.  It’s like visiting a city, but you get to add a whole new country to your list!  If you’re short on time, I recommend visiting two highlights – Le Palais des Princes and Jardin Exotique de…