Thanks, Jennifer @jenniferhunter We did so local traveling outside of Denver when we were there in October and February. We went up to Copper Mountain, and another area, I forget where, and in February we drove to the wedding venue in Pine. We will be staying in Denver though, I have reserved a VRBO there for us, our daughter and husband, and my sister and husband.
The distance to Grand Canyon is pretty much why we may have abandoned that idea. My husband has ALWAYS wanted to go there but from what I hear it will be quite hot there then, plus could still have large crowds of vacationers. I think we would fly from Denver to one of the airports in AZ or to Las Vegas and drive the four hours from whichever. Plans are still being made though.
I have not had trouble with the altitude before. The wedding venue is at about 8500', so hopefully, no one will have a problem with that altitude.