Rothenburg isn't the last word in medieval towns. The heavy tourism there in fact makes the experience a bit Disneyesque.

You can find places similar to Rothenburg in the Rhine/Mosel area. Bacharach itself has a fine collection of half-timbered homes. Check out next-door neighbor Oberwesel, Linz am Rhein (north of Koblenz on the east bank, maybe the best old-world town on the Rhine,) Cochem (Mosel River) and Bernkastel (Mosel River) as well. You'll find old town wall remnants, gates and towers, narrow alleyways, that have been there for centuries. Like Rothenburg, Cochem, Oberwesel and Linz each have their own scheduled Nightwatchman tours (not sure they do them in English, however.)

OK, the town used to be (and may STILL be) THE #1 tourist attraction for the Germans and you can say whatever you want but very few towns actually have a moat and drawbridges (if that's your "thing"). The place is very "medieval looking" at at least what we've long been led to believe is "medieval looking" and then you get to one of the four Kethe Wohlfahrt Christmas ornament outlets and similar sorts of things within those walls and that moat.

The Night Watchman's Tour has been going on for decades and I remember walking the top of the walls back in 1970; it was kinda fascinating then and not nearly as mobbed as it can be today.

It is what it is and the more you know about what is actually THERE the better you'll be able to decide if a trip/stop is worth it. One thing's for sure, just like those "other towns"
along the Rhine, the Moselle, etc., there are gonna be LOTS of people there along with you.

We have been to Rothenburg 3 times (1997, 1999, and 2003). Each trip we flew into Frankfurt and it is an easy drive and a nice stop to get over jet lag before branching out to Munich, Prague or the Rhine. The highlight of the town is the Nightwatchmans tour, which we have done twice. You get such a flavor of what life was like walking the town, and having all the nuances explained by someone dressed in original costume. Now one advantage is to spend the night there since the tour I think is at about 7 or 8 pm and many of the tourists have left already, and then you've walked and can go to bed afterwards. You can walk the wall, visit the Christmas shop, the Punishment museum was great too. In 1997 we were there in July, the other two times in Sept. but not on holidays and it was not really that crowded, but times may have changed and that was 10 years ago. I have also been to and stayed in Bacharach, and I do not feel it is comparable to the feel of Rothenburg. If you go, I would recommend getting accommodations as soon as possible. Only on our 2nd trip did I get my first choice, which I must have done 6 months in advance. There are many nice ones but some like my first choice only has about 6 rooms, if that.
Have a wonderful trip.

Physical Rothenburg is indeed a more complete medieval-town package than almost anywhere else. The OPs question is whether it is so important that her trip should revolve around it - so she has lots to think about, including travel time and other options. And I think some of the other options in the Rhine/Mosel area are very good, especially since they're so close to one another, and some come with extras - Cochem, for example, has its own castle (tours possible) and a show touting the medieval art of falconry, neither of which can be found in Rothenburg.

http://www.burg-cochem.de/english/gallery_exterior.htm
http://www.falknerei-reichsburg-cochem.de/fotobuch.htm

Thank you all for your thoughts on
Rothenburg.

Nothing compares to the package that is Rothenburg. It's deserved fame comes at the price of popularity. It is a little sad to see such a magnificent sight frowned upon by some (the "I don't like to go where TOURISTS go!" kind of tourists) simply because it is so popular.

I don't think anything in the Rhine//Mosel comes close to what Rothenburg offers. I will take the close to fairy tale like perfection of Rothenburg over the ugly barge ridden double tracked rail line waterway that is the Rhine. The Mosel is beautiful but, again, there is nothing along it that matches Rothenburg in either scale or in it's ability to evoke history.