I can only really speak from experience about the courses that Bangor University offers so I’m warning you that this may be a little bit biased! Bangor University offers students a three-language honours in which students can choose from French, German, Spanish or Italian. You are able to make a choice as to whether you want to study the languages at the same level, for example Major-Major-Major or as a Major-Major-Minor as I have done. They organise the course so that you can study the three languages of your choice and you even have the opportunity to study a new language from scratch! As it is a four year course you get the chance to study or work abroad, for this year abroad you have two options – if you study all languages at a Major level then you go abroad for a year and a half spending one semester in each country. The other option is - if you study two languages at Major level and one as a Minor you can choose to spend just one year abroad instead, going only to the countries of your subjects which are at Major level.
Plus pointsThe best bit about studying languages in general is that you can go to different countries and really immerse yourself in the culture. Being able to chat with the locals and order a couple of beers at the bar in a different language is just so satisfying.
Another great thing about studying three languages is that surprisingly learning one language can help you to learn another! As odd as this sounds sometimes I find that the similarities (and even the differences!) between languages can help you to remember vocab/grammar/pronunciation etc. Although this can have its down side too, there are always going to be those times where you just can’t remember a word, say for example in French and all you have floating around in your head is the word in German just to confuse you!
Minus pointsObviously the worst thing about studying three languages is the amount of work that there is. Three times the amount of languages means three times the workload! My advice to you is as far as the workload is concerned is if you want to study three languages then being organised and dedicated are essentially the best qualities you can have. Another quality I would recommend you having if you wish to study three languages is to be fairly laid back, otherwise you may find yourself stressing out over everything!
There are so many good things that learning a language can do for you and studying three languages will just triple the amount of advantages it has, so why not go for it?!