This is a piece of art (I think it is called Umschreibung) by a Finn named Olafur Eliasson. I first learned about these stairs on Flickr but no one listed an address. I went to the Munich Visitor Center and they knew nothing about it but we intrigued so two lovely women helped me look for it - online, phone books, calling colleagues, until we found a possible location - Ganghoferstrasse 29 - not too far SW from the Hauptbahnhof. I went there on a very rainy and cold Sunday morning to find the site pretty much walled off by construction equipment so it was hard to get a clean shot - and the rain didn't help at all. If you are in Munich, check it out - it is a pretty cool piece of art!
Munich is one of my favorite cities to visit - it has a nice feel to it, the people are great - and the beer and wine are pretty good too. I had a chance to stay for three days in October 2009 - great city - horrible weather - it rained about 80% of the time so I ended up spending a lot of time in museums and beer halls. In addition, most of the famous buildings were covered with scaffolding so I ended up with quite an odd assortment of photos. Guess we need to go back when the weather is better!