Getting to Wernigerode is easy - whether by train or car. However, with three adults travelling and a lot of luggage as usual (my fault, I know), car was most convenient and least expensive. So I thought.
The first one was true - most convenient is right. Also, it gave us the flexibility to stop in Aschersleben on the way to and in Blankenburg on the way back. And drive to Goslar, fast and cheap.
However, driving in Wernigerode is a hassle since most of the old town is a pedestrian zone and where it is not they have one-way streets only. So, after finally finding the way to the hotel the shock was the price for the parking: Only parking in the hotel's garage was possible and that was 12 Euro per night. Yuck. And that was even the reduced price for hotel guests! You can imagine what someone pays who doesn't stay there ... and just wants to explore the town for a day. (Granted, maybe you find a cheap parking somewhere. But then it's definitely waaaay outside the old town.)
I recall one guy driving into the garage and complaining very loudly (and not in words I care to repeat here) about the price. 3 Euro for the first hour. LMAO
The get from the town up to the castle you have several options: Most strenuous and cheapest is to walk. It's not a big deal, doable for almost anyone.
As the weather was not co-operating, cloudy and chilly, we decided to take on of the mini trains called "Bimmelbahn" that runs frequently and takes you up (and down) in no time. They start behind the town hall, next to the flower clock. Buy your tickets in advance in the small shop across the street or, if you're tight on time, from the driver. One way the fare is 3 Euro, round trip is 4.50 Euro. I think that's quite inexpensive given what you get for the money. Not only can you ride the train, protected from the ugly weather, no, the driver also tells about Wernigerode and the castle. And I was really impressed how well done that was. Very informative and rhetorically excellent.
It is also a good idea to book round trip because the ride back goes a different route - behind the castle through the woods, passing the so called Wildpark (sort of a zoo) and returning via the district Nöschenrode, hearing more about the history of the town. In German only, sorry.
See schedule at their website, please.
You have to change at Magdeburg to get here by train so it is not the easiest but perfectly do-able.
Inside of town you can use these little carriage, or use your own feets. It`s not a big Town, so its ok to walk a little bit.