Time to give Eagle's Nest it due

Too long, I would skip it if I were you.

You cannot take your car to the Eagle's Nest. You will have to ride on a bus.

I would only visit them on a tour as I believe you get the information to really appreciate/understand the sites. We took the tour from the company run by David and Christine (recommended in RS book). It's lengthy (perhaps 4 hours?) but extremely valuable information. If you don't have the time for the tour, then I would say do not go.

Kevin,

As I recall, there's a car park at the Dokumentation Centre & Bunkers, but as mentioned earlier I don't believe that will be an option going to the Eagle's Nest.

I would also recommend parking the car in Berchtesgaden and taking the tour with Eagle's Nest Tours as you'll learn far more about the history, which will make for a more rewarding and memorable visit.

if you have a car it is easy to park at the document centre and visit it ( recommended) . the buses that go to eagles nest also leave near the same car park. you buy the tickets near the car park. you have to catch the bus up to eagles nest from the car park. (ie: leave your car there)
unlike the earlier replies, I think you can easily do both by yourself. it may save time and you can still enjoy looking around yourself.
the document centre and bunkers are full of information with a audio guide. there really is too much info. you can spend many hours there if you want to take it all in. but even a hour or so would do, if you were rushed for time.
going up to eagles nest would be best on a nice day, as the view is part of the experience. when we went there was a bit of a line up to catch one of the 4 buses that ascend the mountain. and then we nominated a time for our return bus ride. once again allow a good few hours. more time than needed at the document centre.
both are very good to visit. highly recommended.

hope this helps.

Thanks for the advice everyone!