Chatel and the surrounding area is a paradise for walkers. If you really want to work hard the area is very mountainous, but by using the extensive ski lift system you cut out most of the uphill work.
The ski lifts open in the summer to whisk walkers to the local summits in no time. That leaves a relatively easy walk across the mountains and back down to the village. Many of the mountain restaurants open in the summer, so you can stop and take a break in the summer sun.
Here's a link giving details of the local walking maps available from Chatel Visitor's Centre
http://info.chatel.com/the-maps-and-topo-guides.html
For a short evening stroll we recommend walking up to and around Lake Vonnes.