Its majesty, state of preservation and special construction features make it a unique place in Sardinia. The granite complex of Su Mulinu Vezzu is the only survivor of seven water mills operating on the Bisine river in the early 20th century. ‘The old mill’ is located less than a kilometre from Olzai and is surrounded by holm oaks, oaks, cork oaks and Mediterranean greenery. It is an impressive work of pre-industrial hydraulic engineering, built around the mid-19th century for the grinding of wheat and barley. You can admire a mill with a vertical waterwheel and its structure is divided into two complementary parts: the large wheel is between two high walls and drives the stone necessary for milling. Above it, embedded in the stone, a channel collects the water captured from the river through a stone and rock embankment. Thanks to the slope of the channel, the water falls onto the wheel, making it turn. The actual mill is inside the adjacent room.

Inside it, you will notice the stone floor and the wooden gears that activate the mechanism capable of setting the large grindstone in motion. The room also serves as a small museum, where typical milling objects and tools are on display. Flourishing agricultural activity was the basis of the economy of Olzai, the prosperity of which was also demonstrated by the high percentage of people with degrees between the end of the 19th and beginning of the 20th centuries. In 1921, a devastating flood swept away all the mills except the Vezzu, which nevertheless suffered serious damage and was abandoned. Between 2003 and 2004, the Municipality of Olzai took action to restore it. Today, the mill works and is activated for wheat milling demonstrations. A visit to the museum is also an opportunity to explore the Olzai landscapes. To the south-west of the town, stands Mount Gulana, a destination for trekking and mountain biking excursions, which has stone blocks on its summit: they are evidence of a castle, perhaps of Byzantine origin and the stage of fanciful legends. It is said that a treasure was hidden in the basement.

Olzai is the traditional destination for Autumn in Barbagia, an event during which you can taste the typical products of the area, admire the local artisans and observe su Mulinu Vezzu ‘at work’. The fourteenth-century Church of Santa Barbara is also worth a visit. Inside it, you will find the ‘Retablo della Pestilenza’, a work by an artist known as the Maestro d'Olzai.