Merchandise Mart. Many old buildings are bought and reused for other purposes instead of being demolished, which saves money, energy and helps maintain culture.

The seven floor Merchandise Mart, now a Macy's department store taking up what feels like an entire square block. 

Deserving Chicago culture. 

Frozen river that cuts downtown Chicago. Moveable bridges were build over this river so that boats could enter but had permanent connections for cars and pedestrians. 

The bottom half of Marine City is parking (since there isn't possiblity of underground parking along the river) for the apartments in the top half of the building, making it sustainable in itself in terms of space. 

Multi purpose constructions. 

Marine City borders right along the river that passes through downtown Chicago.