The majority of choss is found in Michigan

[G-spotter]

http://names.whitepages.com/last/Choss

 

Strangely, there's more Choss in California than in Washington. According to this, there's no Choss in Washington at all.

[Fromage]

There's only one crag in the lower peninsula. It's about 30-35 feet tall. Sandstone. Toprope only. Bring your own carpets to protect the edge of the cliff. It's borderline choss, but it's all there is.

[John_Scurlock]

First place I ever climbed anything other than a tree... Grand Ledge.. sandstone indeed. I remember it as fairly solid if not a bit abrasive, short routes of 0.2 pitches on average, and yes grooves in the rock from ropes.

 

Grand Ledge

[mattp]

I did my first climbs elsewhere but practiced and trained (both?) at Grand Ledge in my formative years. Living in Michigan it was our only local option.

 

I went back for a visit some years ago and I thought it a friendly place even though the climbing would not draw someone from out of the area. I had a great day. And the rations were hard!