First is the Kroepke clock. Do you remember the meeting spot under the horse's tail? If you are not meeting at the horse's tail in Hannover, you are probably meeting at the Kroepke clock. Kroepke is the name of the biggest and busiest part of Hannover's downtown. It's basically a square with the opera house on one side and a pedestrian shopping street on the other. You can usually find a street musician or two there, along with a balloon man and a sausage vendor. There are usually at least ten people standing around the clock, waiting to meet someone.
It's hard in Hannover, and I think in most of Germany, to really lose track of what time it is. There are clocks all over - on church steeples, on the front on the Rathaus, at tram stops, and sometimes even outside of storefronts, hanging over the sidewalk. The Germans are punctual people. If you are meeting friends at the clock, they can definitely tell when you are running late.
The next landmark is a trio, a trio of buxom hippie lady statues. They are the Nanas. On Saturday mornings, the flea market opens under and around them, along the Leine River banks. The Nanas were created by French artist Niki de Sant Phalle in the 1960s and have been in Hannover since 1974. The Nanas are meant to emphasize feminism and women's rights, so they are very... rounded. These "everywomen" are named Sophie, Caroline, and Charlotte (I'm not sure which is which). They also sport some cool psychedelic outfits. While the Nanas were controversial when they first arrived, now they are some of the most loved landmarks of Hannover.