This place is a dump. I booked on Priceline, because the last time I booked a Priceline hotel in Chicago, I got the Westin and loved it. Despite having paid for Priceline, I ate the money I had already spent and called for a reservation at the Westin and went there for the weekend, instead. I didn't regret it for a second. You will be disappointed if you stay at the Millenium Knickerbocker because you are paying for a Holiday Inn at the price of a Westin when you could have the real deal for just a little more. The location is not worth the place being old and so unimpressive. There are enough hotels near the loop (and near a train/bus stop if you need to move around the city inexpensively) that you should not spend the money on the Millenium. Do not waste your time and stay here--this is a trap because of its location, but it's not worth it. Really.
