Typical activities are hiking and horse riding (300/1000som per hour/day, for guide/horse-guide 1000/1400som per day), which is easiest to arrange at the tourist-focused camps at Batai-Aral and Jamanechki though also possible at most yurts with negotiation if you speak some Russian/Kyrgyz. Birdlife includes vultures, numerous raptors and waterfowl, including the Indian mountain goose.
If trekking without a guide, the Kyzart–Tuz-Ashu route is the easiest one-day option while the Kilemche–Jamanechki–Batai-Aral route makes a good two-day alternative. With a guide, starting from Kyzart or Jumgal then looping around via Tuz-Ashu and Uzbek-Ashu makes a fine two-night out-and-back option. Horses can be hired for any of the above hikes, but aren't strictly needed if you've left your main luggage in Kochkor or Naryn and are travelling light between yurtstays. These areas are criss-crossed by shepherds' trails, however, so a map of the area is handy for route-finding.
Steep-sided green jailoos fill the Kilemche (Klemche) Valley, which runs parallel to the north shore of Lake Son-Köl. There are three small family yurtstays well up on the south side of the valley, each about 25 minutes' walk from the 'road' from Kyzart, but up separate side valleys.
Although not on the lake itself, sleeping or arranging lunch at Kilemche makes an excellent addition to the Son-Köl experience. To walk to the lake from here, take the side valley that leads south around 10 minutes' walk east of the farthest yurts. The path seems to fade at first but becomes clearer up higher as you approach the impressive Jalgis-Karagai Pass. The lake is visible from the top. Continue straight ahead into the gulley for Tuz-Ashu, or contour diagonally left on the bigger horse-trail for Jamanechki (around four hours' walk from Kilemche).
To reach Kilemche from Kyzart or Jumgal takes between four and five hours on foot or horseback along a well-worn motor-track, or is an 800som taxi ride. Alternatively from the Kochkor–Chaek road at Jumgal village (around 3km east of the Kyzart Pass), there's a delightful if more strenuous five-hour hiking alternative. Head diagonally following tyre-tracks inexorably upwards towards the obvious zig-zags of the sheep-scuffed 3525m Chaar-Archa pass. The pass is topped by a stone inscribed Chölbay Bulagy. The road and path (better) diverge here but later re-combine. Follow the obvious trail down to a small metal bridge, cross that, then contour up and around a high bluff on the far side of which you get views over the splendid Kilemche Valley, but first you'll need to veer slightly eastward to cross the river at the valley bottom by the Tash-Saray stable complex. One short section of the descent can turn to mud in heavy rain but otherwise the trek is pretty straightforward and magnificently peaceful.