"Microstates" refers to legitimate countries that happen to be really really small. Some are tiny islands (most in the Pacific or Caribbean) but five are in the continent of Europe. I saw Vatican City while backpacking after college, but I'd never visited the other four:  Andorra, Liechtenstein, Monaco, and San Marino.

Old fragmented Europe (circa 1400)

In past centuries, as Garibaldi, Bismark, Napoleon, and others consolidated the messy map of Europe, these places cleverly escaped absorption ― using shrewd ploys and (for three of them) helped by remote and mountainous locations.

Andorra, Liechtenstein, and Monaco are called "principalities" because they modestly just call their monarch a prince. For such tiny domains to be "kingdoms" with kings would seem awfully pretentious and might be provocative to their larger neighbors.

In addition, there is the (monarch-free and wonderfully named) "Most Serene Republic of San Marino," arguably one of the oldest republics in the world.

So just how small are each of these four countries?

Country	Population	Sq Miles	Km2
Andorra	76,000	181	468
Liechtenstein	37,000	62	160
San Marino	32,000	24	61
Monaco	36,000	0.8	2

For comparison, the District of Columbia (Washington, DC) is 68 square miles (177 km2), and thus larger in size that three of these four; plus DC has roughly 632,000 residents. And Luxembourg is a relative giant with 998 square miles, over five times larger than Andorra.

While all are small, variation among them is still substantial as shown in the table above and on my rough maps on the left.

Are these genuinely "sovereign countries" or are they like Pluto not quite the real thing? Each has "special relationships" with their big neighbors (Monaco with France; San Marino with Italy; Liechtenstein with Switzerland; Andorra with Spain and France), but:

• All four are full members of the United Nations.
• All four have full diplomatic recognition from both the United States and United Kingdom.

For various reasons, none are formal members of the European Union, although they participate in certain EU arrangements and have essentially open borders with the adjacent EU countries. One big reason they do not want to be EU members is their current lucrative positions as "tax havens," offering low or no income taxes, low or no VAT taxes, banking secrecy, etc.

In August of 2013, I finally spent some time exploring each of these microstates:

• Liechtenstein (in the Alps mountains; travel via Zurich)
• Andorra (in the Pyrenees mountains; travel via Barcelona)
• Monaco (on the Mediterranean at the base of the Alps; travel via Nice)
• San Marino (in the Apennines; travel via Rimini via Bologna)

It was not a simple jaunt. None have airports and only Monaco has a train station. But, using bus connections from the major airports listed above, I succeeded in visiting them all. My favorites were Monaco and San Marino.

P.S.
This post is about microstates on the continent of Europe. Nothing against Malta, out in the Mediterranean, the smallest member of the EU and a bit smaller than Andorra. On my way to Libya in 2006, I visited Malta for a few days. I want to return to see more of its islands.