On the second day of camping my older sister and I took our kids out to the Dee Wright Observatory which is just a short drive from Sisters, Oregon. From there you can see two of the Three Sisters, Mt. Jefferson, Mt. Washington and several of the major buttes and landmarks. It was a beautiful clear day and perfect for the views.
The building was made from the lava rocks at the site and the "castle look" got the kids excited to play Save the Princess and other sword fighting games. They all had a good time playing here.
Up on the top there is a dial to tell you which direction to look for each sight, how far and how tall they are.
The view for the North and Middle Sisters is always my favorite.
In the lower room of the observatory it's also fun to check the patterns of the water stains on the ceiling. It's not exactly one of the attractions but I think it's very cool.