You can park in the millennium park parking garage, but I would suggest taking public transportation.
App, but public transit always preferred, if possible
I use the underground garage at millennium park. However, traffic is heavy and parking expensive. Buses stop on Michigan ave nearby. The El is close by. For efficiency, UBER my recommendation
What everyone else said about public transportation.
I would use an app like spothero to get the best parking or take public transportation when possible.
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