S'Argamassa Roman Aqueduct

The wall runs dead straight across an open field for more than 400 metres, and for centuries it has done a second job as the boundary between the parishes of Sant Carles de Peralta and Santa Eulària des Riu. At first sight it reads as a tired old field wall. The interest is inside: a series of overlapping conduits that carried fresh water from a spring near the site northeast to the sea.

That water fed a coastal industry. Down at the shore it was channelled to a fish-salting works where garum, the fermented fish sauce traded across the Roman Mediterranean, was made, and a steady freshwater supply at an anchorage was worth a great deal to ships of the period. The aqueduct came close to disappearing. In 2014 a local association, Rasar, won a long campaign to rescue it, including having a wall built over it taken down.

• The remains are modest: weathered stonework, with an inscription in front so faded it can no longer be read.
• The site is hard to find and poorly maintained. Save the location in a map app before you set off.
• There are no toilets at the site. The nearest, about 735 m away, are for customers only.
• There is no drinking water and no information point nearby, so bring water with you.

The aqueduct stands in Santa Eulària des Riu, about 15 km from Ibiza Town. The nearest car park is about 185 m away in a straight line; a second one, about 258 m away, is for customers only. Coming by bus, the two nearest stops sit about 540 m and 570 m away in a straight line.

The site is hard to find on the ground, and the inscription in front is faded past reading, so have the location pinned on your phone before you leave the car or the bus.

Best: early morning or late afternoon, when low sun rakes along the wall and picks out the stonework.

Avoid: the middle of a summer day.

An open field gives little cover from the midday sun, and there is no drinking water nearby.