This is Alexanderplatz Station.
You can transfer to U5, U8, S5 and S7.

This is the U2 line toward Pankow. The Next Station is Rosa-Luxemburg Platz heading toward Pankow Station.
This is the U2 line toward Ruhleben. The Next Station is Klosterstr. heading toward Ruhleben Station.

Alexanderplatz is the home of many events. It's also the center of quite a bit of activity in Mitte. Many main Bahn lines come through this station, and not only is there a large above ground shopping center that has all kinds of stores, but there is even a traveller's bathroom place where you can shower, etc. Underground the stations amenities continue, providing more options for people's everyday needs to more obscure needs. Across the street is also the Alexa mall offering even more choices. South of the square there is yet another shopping complex that mostly caters to tourist needs.

The real items of interest here, primarily consist of the World Clock, the TV Broadcast Tower (Fernsehturm), Neptun Fountain, and Marien Church. In the vicinity within easy walking distance is Museum Island, which has many interesting museums to visit, and a little further on, will bring you to Humboldt Universität where some famous greats have both attended and taught.

Another interesting attraction is the Park Inn, which has an interesting attraction allowing you to free fall from the side of the building, take a slower horizontal walk down the side of the building, or other options. Get your details about it here.

Throughout the year, various festivals and markets will pop up as well as concerts and other events. There is typically something going on here, even if it is just street performers. Near the TV Tower you can rent bikes and take a tour of the city. Some of the bikes come with a keg on board that everyone can drink from while they are riding.

There is too much to list about Alexanderplatz as so many things happen here.

Random Experience:

After living at Schlactensee Studentendorf, I moved half a block from here for two months. It was nice being able to easily get down to the events going on here and see what was happening if I was really curious. My window actually faced Alexanderplatz sort of, so I only had to open it and peek around the corner and I could see if anything interesting was happening. Personally it wasn't my favorite place to live, but I definitely had a good time living there. I met a lot of interesting people and learned that here in Berlin, Greeks and Turks could be friends, but not back home. Interesting how these sorts of cultural rules affect people.

Another item of note, I actually bought my boots that I still have from Alexa Mall. I purchased them in 2012 at the end of December and wore them nearly constantly while in Berlin. They are still in great condition. I was kind of joking when I said they'd last for a long time, but I guess I wasn't really.

Last thought, if you're an American and you're in Berlin and for some reason you decide you need more soda that they typically sell you (because almost no where does free refills), then head over to McDonald's on the second to top floor of Alexa Mall. There and only there, I found unlimited soda refills. It was extremely novel and I used it twice when I was really craving a feel for home, but by the time I'd discovered it, I'd mostly gotten over that need to consume large amounts of it. I mostly did it for the novelty.

View attached image.

View attached image.

View attached image.

View attached image.

View attached image.

View attached image.

View attached image.