Highest Free View of the City

I’ve moved to Chicago about 3 months ago to start college and I love looking at the skyline. I live in Lincoln Park and I usually go to the top of the Children’s Memorial Hospital Parking lot to get the best open air view of the city and that is roughly nine stories up. I’ve taken quite a few really good pictures from there and it’s a cool little spot.

Bt I’m wondering if any chicago photographers and other skyscraper and urban-loving chicagoans know of any other great free high up places with really good views of the city or lake or both? I’m up for a little exploring even in this weather…