Take care about the correct spelling of the name of this city. English-speaking people tend to omit and ignore the two dots on the u. However, MUNSTER is the name of a small town in the Lüneburg heath north of Hannover and if you buy a train ticket to or book a hotel room in “Munster”, or enter the name into your navigation system, there will be a surprise for you…
If your keyboard does not have the “ü” (which is an Umlaut and turns the vowel into a completely different letter and sound), there is an alternative spelling which is correct and acceptable and understood: insert an extra “e” after the U and make it MUENSTER.
You will also notice that there is more than one Münster in Germany. The name derives from Latin monasterium (monastery) and there are several, although all the others are small villages. If you need an exact definition (on the Bahn website, for example), Münster/Westfalen is the right one.
Be careful when walking on the sidewalks in Munster. There is a lane on the sidewalk that is for cyclists, and it's not always obvious. Most of the bike riders will ring their little bell at you if you are in their way, some will ring their little bell angrily, and some will practically run you down.
In my mind, pedestrians are to be respected above all, but many cyclists are riding the high horse, so to speak. Yes, they are annoying, but I suppose it's rules of the road...or sidewalk.
Please note that while some castles are completely open to the public (like Nordkirchen, Raesfeld, Lembeck, Anholt), many are in private ownership. The interior is often not open for visitors, sometimes not even the inner courtyard. This means you can only walk around the moat (or a part of it) and admire the architecture from the outside. This applies - for example - for Haus Borg, Schloss Darfeld, Schloss Varlar etc. The local tourist office might be able though to arrange a guided tour for groups in some cases.
Münster is a student town and wery bike-friendly, but the many cyclists are easily overlooked when you are taking photographs or crossing the street. So take care not to run into a cyclist while admiring the sights of Münster. Be extra careful when you drive a car, usually there is a seperate bike lane on the road you have to watch!
Since there are so many bicycles around, you must be really careful as a pedestrian and as a car driver as well! It is not always THEIR fault, though: we caught ourselves walking on the bicycle paths, which was nice and spacious!!!!
Avoid Aasee area (park) at night.
It is quite an obvious tip.
Anyway, there is no reason to wander around this dark area late, unless you are looking to getting into trouble or into drugs.
During the day, you can walk around without trouble; in fact it is a quite common to see lots of people walking / cycling around on sundays or afternoon if the weather is good.
Be carefull, maybe you will like it so much that you will like to stay longer!
Some other places I recomend to visit around the old town are:
Kiepenkerl, Erbdrostenhof, Clemens Church, Picasso Museum, Sant Pauls Cathedral with the Astronomic Clock in the middle of the principal market, the Lamberti Church, the Town hall and of course take a bike and cicle around the promenade and the canal!