Vacation time according to "Bundesurlaubsgesetz"

I recently signed a contract with a company for an internship in the next months. It states that the only vacation time I get is the "Bundesurlaubsgesetz." I know this has something to do with vacation times mandated federally for each individual state so we don't all crowd the autobahn at once. However, I have no idea when this means I get to take my vacation :-(. I'm trying to plan family visits out here and it would be nice to know when they should book flights.

I'll be working in Hildesheim, Niedersachsen.

Any help is appreciated!

The Bundesurlaubsgesetz isn't referring to when you can take your vacation, but how many days you get.

In your case (less than one year contract), that means you get 2 days per full month that you've worked for them, ie maximum 2 days possible after the first month, maximum 4 days after the second, maximum 6 days after the third and so on.

Timing is not mandated at all by law, however there are some guidelines (for the employer when granting you vacation): You may take your vacation (the days you've collected up till then) at any point you want after the first month, however the employer may restrict this - e.g. if your company has a general holiday week around Christmas - or in Summer - you might be required have to take your vacation during that time, if possible.
There might be some more restrictions in your contract - e.g. no vacation during the first three months or similar.

Note that this is all about paid vacation.

Thanks that was very helpful. So assuming I start the middle of February, this means I wouldn't be able to gain those first two days until late March, right?

I do remember reading somewhere that vacation times for each state are regulated so they don't all take to the Autobahn at the same time. Has anyone else read about this?

You're thinking of school holidays. The different states have their school holidays at different times to spread the load a bit. Here's a list.