I'll be there next Tuesday and Wednesday. I will have approximately 12 hours of free time over two days.

I'll be staying at the Crowne Plaza on Carondelet Ave (which is actually Clayton, MO, but appears to be the same as St Louis). It's about 8 miles from the Arch.

Anything I should do...see?

Going to the Arch, for sure. Just to say I've been there.