I'm not reviewing the SI-Center as a hotel as some other reviewers have done, because there are two hotels within the property, which are worth reviewing separately. I have no problem with the great staff at the Millennium Hotel who have made our long-term stay quite comfortable. I'm reviewing the SI-Center as an "attraction" or destination for tourists, in which case 3 stars is rather generous.
The SI-Center is a complex that includes two musical theaters, a modern movie theater, and many restaurants and a few bars along with a large spa and two hotels. There are also some very small shops. If you just want to see a musical or a movie (in German, of course) it's a convenient place to go, as it's right on the U-Bahn line, and you have a lot of options for food before or after the show, albeit none of the options are particularly good. The spa, "SchwabenQuellen" is more expensive than the mineral baths that are all around the area, but it's also themed really nicely and is a cool place to visit.
There's virtually no reason to come here otherwise, however. As a destination simply for food, clubbing, or shopping it leaves a lot to be desired. The best restaurant in terms of quality is the "Schlossturm" Brewhouse, which serves hearty Bavarian and Swabish food and good house-made beer in large quantities. However, there are tons of places to get good German food and beer in Stuttgart, and Schlossturm is not so great that I'd recommend making the trip specifically.
The "fancy" restaurant, Don Giovanni, has fancy prices but the food is just eh. The other restaurants are worse, though. The Irish Pub, "The Dublinner" seems popular, particularly with our fellow Americans, but the service is surly and the food is simply reheated frozen food. There's several better Irish pubs in Stuttgart proper, so again, no reason to make the trip. Ditto for "Die Weinstube" although the service there is at least attentive. My favorite bar is Intermezzo, which sometimes has an entertainingly cheesy piano guy singing American standards from the 30s-80s, and offers one of the better whiskey selections I've seen in Stuttgart so far.
There is also a "Phantom of the Opera" themed club only open on weekend nights. It's baffling. It seems very, very popular and sometimes charges a cover, but wasn't particularly cool. Again: there are tons of better options for clubbing that don't require a 25 minute U-Bahn ride, so why would people come here? Haven't figured it out yet.
The casino was incredibly boring, and it was somewhat insulting that they charge you a (small) fee to enter. All the slots are video, and there are some table games, but not a lot of excitement.
Yet despite this and the downright silly architecture, locals seem to really enjoy the SI-Center as they amble incredibly slowly through passageways, taking it all in. There might be some invisible cultural barrier preventing me from seeing what's so great about the SI-Center, because I'd much rather spend a night out on the town in Stuttgart-Mitte than hang around here.
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