Every year their is a large event held at the Merchandise Mart called NeoCon, The event is North America's largest design exposition and conference for commercial interiors. Locals that are in the design profession make sure to get involved and attend the event . The event is usually in June so visit the Merch then!
The Merchandise Mart is where you go to shop the showrooms and get inspired for your latest interior design styles. Even if you don't buy anything it's a great place to see what's happening and get inspired. The building is large and historical. It is know for once having it's own postal code.
The CTA train station is pretty fun and the view from the train ride is great. I totally recommend taking the train to the Merch Mart