Santa Eulària gets its suffix, 'des Riu' (of the river), from the reed-fringed stream just west of town. There's usually little more than a trickle of water, but it is the only river in the Balearics. This information centre, in the restored medieval Molí de Dalt mill, explains the irrigation systems first developed by the Moors and which flourished along Santa Eulària's riverbank. It's just off the Passeig des Riu (Riverbank Promenade), 600m northwest of Puig de Missa.