Santa Eulària des Riu is a coastal town on the south eastern coast of the Spanish island of Ibiza. The town is located on the designated road PM 810. Santa Eulària is the third largest town on the island and also has the only river on the island which flows into the sea at the western end of the town.

Ibiza is a Spanish island in the Mediterranean Sea off the eastern coast of the Iberian Peninsula. It is 150 kilometres from the city of Valencia. It is the third largest of the Balearic Islands in area, but the second-largest by population. Its largest settlements are Ibiza Town, Santa Eulària des Riu, and Sant Antoni de Portmany. Its highest point, called Sa Talaiassa, is 475 metres above sea level.