Which is the only European country that is doubly landlocked, meaning all neighboring countries are also landlocked?

Liechtenstein is indeed the only European country that is doubly landlocked. This means that not only is Liechtenstein itself landlocked, but all of its neighboring countries are also landlocked. Liechtenstein is bordered by Switzerland and Austria, both of which do not have coastlines along any sea.

This unique geographical feature makes Liechtenstein particularly interesting from a geopolitical perspective. Its landlocked status means that it does not have direct access to ocean trade routes, which can impact its economy and transport. In contrast, other options listed, such as the Czech Republic, Andorra, and Montenegro, have at least one neighboring country that has a coastline. Thus, they do not qualify as doubly landlocked. Understanding these geographical distinctions is crucial in geography, as they highlight the varying levels of access to maritime resources across different regions.