There are two marked paths from the village - we turned right at the start of the old town which led up a stony path, quite steep. It was marked as 25 minutes, which was about right. Lots of informative signs on the way (in German & English) give you a sense of the history and some of the myths surrounding the castle over the centuries - and give you the chance for a breather whilst climbing. The alternative route, which we did as the descent, is mainly stone steps which lead to the centre of town (this route is marked 20 minutes for going up).
The views from the top are wonderful, and make the climb well worthwhile. The ruins are - well, just that - but the trip is recommended for a spot of exercise before taking a refreshing drink and bite to eat in the lovely old town. One thing to note - based on Trip Advisor's rankings we had planned to take lunch at the Sänger Blondel restaurant, but were disappointed to find that it does not open on Sundays, despite the popularity of the town with weekend tourists.