It is funny, but in Finland you find one of the hardest languages to learn for an english-speaking person. Try to learn finnish and you notice why. The whole structure of finnish language is totally different from english.
In english you do many thing with prepositions such as at, in, on, from and so on. In finnish you do not have any prepositions. You have to express all these things with something the finns call “sijamuodot” (Grammatical case).
This is known all around the world: According to a freshly-released list Finnish is among the group of languages the FSI considers to be the most difficult for English speakers to learn. (Source: US State Department’s Foreign Service Institute according to YLE news)
You can have more information about the hardest languages from here.
In the following picture you see the craziest example (click to enlarge). Feel free to try and pronounce it. And learn!