The Regional Department of Infrastructure and Housing of the Andalusian Government has completed conditioning work on the HU-9100 from Encinasola as far as the provincial boundary with Badajoz, a route of almost 6 kilometres running entirely through the municipality of Encinasola, in the province of Huelva, within the Sierra de Aracena and Picos de Aroche Nature Park.

The works entailed an investment of 3.8 million euros, and comprise the conditioning of the existing highway in both plan and elevation, in order to increase road safety and user comfort. The existing route was thus exploited in all sections where this proved possible, while bypasses were built where bends needed to be straightened.