Fine state park, beautiful views of serene Mirror Lake which is quite nestled into the dells of the area. The park has tons of hiking trails all over, nothing too hard, and typically MUCH less busy than Devil's Lake SP not far from here.
While our party had children and thus nature viewing is not always possible due to our ambient noise level, there are always tons of signs of animals here, from Pileated woodpecker gouges to beaver chew marks on the trees above the lake. There is plenty of nature in the area to be seen, there is even some history. The Pulpit Rock trail includes some history about the neighborhoods that were once planned/built here for socialite families of the region. Somewhat interesting, nothing that will blow you away.
The facilities at the park front office are the best in the park, with the rest being the typical pit toilets.