The headline for this question could have been "How many days is needed in Liechtenstein?", but the answer is really in the hours rather than the days. There's not much to do there. I felt done with it after less than two hours, but if you want to fully experience it you could spend up to six hours. More than that I can't see any reason to stay unless you want to hike the mountains, but in that case, there are better options in the Swiss Alps. I still feel that it was worth it to take the detour to visit one of the smallest nations in the world.

Liechtenstein is one of the six European micro-states, along with Andorra, Malta, Monaco, San Marino, and the Vatican. In terms of the area, it is the fourth smallest state in Europe at only 160 km2 (62 mi2). It also has the fourth-smallest population in Europe with only 39 000 inhabitants. In other words, this mountainous country located between Switzerland and Austria is very small.

You won't need a visa to go to Liechtenstein. They are part of the Schengen Area, and so are surrounding Austria and Switzerland. The only way into the country is by land. There's no airport and there's no port. Your options are car, bus, train, or walking. If you go by train you will arrive in Schaan, which is the largest settlement but not where you want to be as a tourist. Vaduz is where most of the tourist attractions are found.

It's easy to find parking in Vaduz. Find one near the main street of Städtle. A suggestion is the Marktplatzgarage. Most sights are found near or on the Städtle such as the St. Florin Cathedral and various Government buildings. There are also a few museums. If you want to visit them you will, of course, need more than two hours. There's an Art Museum, a Post Museum, and a small National Museum.

The main sight of Vaduz and Liechtenstein is the Vaduz Castle overlooking the country and valley. There's parking if you drive past the castle and a little bit further up into the mountains. You will then have to walk for a few hundred meters until you're in front of the castle. However, it's not open to the public and you can't visit inside. It's still worth driving up there for the views of the valley. There's an observation point near the Castle which I can highly recommend walking to.

Liechtenstein and Vaduz are quite suburban and not a dense historic town. So after you've seen the sights around the Städtle and then a short visit up in the mountains near Vaduz Castle, you are pretty much done.