Mills in Altoaragón - harinero

Las Bellostas

Las Bellostas is not anywhere near any mayor road. It is probably best to start from Boltaña and take the road towards Lanave and the Puerto de Serrablo (A-1604). After 11 km on this narrow and winding road there is a branch to the left towards Las Bellostas and Paúles de Sarsa. It is before the highest point of the Puerto at km-39. Follow this narrow road until you reach the village. At the entrance of the village turn right and once more right and you should reach the end of the metalled road in the lowest part of the village. Find the markers of the GR-1 and follow the trail to the West. The trail will cross a gravel road and from then on you should follow the road going down into the valley of the Río Balces (or Isuala) where the mill is. It is a walk of about half an hour from the village.

Pallaruelo, in his book Los Molinos del Altoaragón (1994), has dedicated several pages to this striking construction and its waterworks.

Pictures: V.1995, 21.VII.2015, 4.X.2016

(11) The mill with the pressure pit (high section left) seen from the North.

The waterworks are not any less impressive than the mill proper. The pressure pit, the length of the canal, the size of the dam, everything is oversized and must have cost enormously to build.
The highest section of the mill (11) leaning against the slope contains the cubo (pressure pit, 13). The cubo has a diameter of about 200 cm (14) which is one of the widest we have seen in the region — f.e. the cubo in Nueno is only 100 cm wide.

(12) Mill pond with pressure pit (cubo).

(13) The pressure pit (cubo).

The bottom of the cubo is hidden by plant material, but the visible part of the cilinder is about 6m deep. The top opens to the mill pond and therefore has a cross-section in the shape of an Ω (13).
The position of the mill high on the bank makes for a canal which must be very long. There are still stretches of the canal discernable between the dense vegetation: enough to trace the canal back to its beginning — some perseverance is needed!

(14) Cubo.
(15) Stone plate on which dam was built.

About 600 m upstream (see 20) the remains (15, 16) of a dam, the first one of two, can be seen. At the capture point the canal is about 4 m above the river bed. In order to be of any use, a dam at that point must have been at least 4 m high. Down in the river is a huge stone plate (15, 16) which served as the base of the dam. From one end to the other (16) a row of 12 huge holes is carved in the stone.
The holes are about 1.5 m apart from each other and on average have a ∅ of 60 cm. Two measure 70-75 cm and one only 50 cm. Several of the big holes are paired with a narrower one of only about 30-35 cm. Huge beams (entire trees proba­bly) were fitted to the wider holes. Smaller brace beams planted in the second row of holes were meant to counteract the pressure of the water.

(16) Base of the first dam: a row of 12 holes across the river.

There must be more holes hidden below the vege­tation, because the width of the river is double the visible length of the row.

It is unlikely that a construc­tion of this height and width could withstand one of the flashfloods which are not uncommon in this parts. It must have been a battle without end. That may have lead to the con­struction of a second dam about a quarter of a km further upstream (see 20).

At the position of the second dam (18) the river is narrower and the boulders at each side are only 2 m tall. A dam at this place will be much more modest and manageable. There is a line of holes similar to the previous dam, but their diameters are much smaller. They measure only 40-45 cm (19).

We could not find the intake and it was impossible to find a channel that could have carried the water to the canal that we had followed from the mill to the first dam.

(17) The river bank behind the dam is reinforced with walls of stone.

(18) The second dam.

(19) Holes of the second dam.
(20) Aerial view of mill with both dams
© PNOA 2006 -

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