A small collection of Tibetan-script petroglyphs and accompanying Soviet-era graffiti make for a nice 3km walk (one-way) from the nearby highway, but the extended 8.3km that loops back towards Ak-Sai village (14km west of Bokonbaevo) takes in some extraordinary views of red-rock hills with the deep blue of Issyk-Köl beyond. It's scorching and shadeless in summer, so take plenty of water, and the petroglyphs are hard enough to find that it's absolutely worth contacting CBT for a guide.
Don't confuse these with the Tamga Tash petroglyph stone, near Tamga village, at which the landscape and glyphs are both significantly less enticing.