Parc naturel Thal, Protected area in Solothurn, Switzerland.

Parc Naturel Thal covers the whole Thal district in the Solothurn Jura, a gentle landscape of the eastern Folded Jura across 139 km² and nine communes. Beech, fir-beech and pine forests alternate with dry meadows grazed by cattle, while the valley floor between Balsthal and Herbetswil is mostly cropland. The Dünnern and its largest tributary, the Augstbach, run through the park.

The park's recent history centres on the return of European bison: a 50-hectare enclosure southeast of Welschenrohr was approved in early 2020, and the first animals arrived from Wildnispark Zürich in autumn 2022. The herd grew from five to ten, with two calves born in 2023 and three in 2024, and the enclosure was enlarged to 100 hectares. The project tests whether bison could live freely in the Jura.

The nine communities within this space maintain traditional crafts and farming methods that remain visible in the landscape today. These practices shape how the land looks and how people continue to live here.

The park covers the whole Thal district in the Solothurn Jura, 139 km² across nine communes, with the Dünnern flowing through its upper half. The bison enclosure southeast of Welschenrohr is looked after by the ranger at the neighbouring Sollmatt farm, who answers questions and advises visitors on site.

Educational programs explore milk production, nutrition, and forest ecology through guided experiences that show visitors how local products are made. These programs reveal the connection between daily life and the natural environment here.