When driving into the park off Michigan Ave there's a huge hole on the right side just as you are coming out of your turn. Also watch for cars going slow at that spot, lots of small craters on the road. West loop is best, I avoided most of the east loop, rode all of the two track. From what I could see some sections are rock hard dry, and some by the parking lot are greasy. If the rain holds out tomorrow, I'm thinking more might be rideable in the afternoon.