Things to do while visiting

In about a month I will be visting a friend in the area for about 6 days with a third friend. The local friend will have to work for at least part of our visit, so my friend and I are looking for suggestions of things to do while he is working. We already have a few hikes planned and will definitely be visiting local breweries. We were looking into white water rafting, but it seems we will be there a few days before most places start doing rafting trips. Basically what I'm looking for are suggestions of things to do/places to visit during weekdays to kill some time and get to see the area. Thanks!