Erythropotamos

Erythropotamos (Ερυθροπόταμος) Luda reka (Луда река)
Native name	Erythropotamos (Greek) Ερυθροπόταμος (Greek) Luda reka (Bulgarian) Луда река (Bulgarian)
Location
Countries	Bulgaria and Greece
Physical characteristics
Source
• location	Eastern Rhodope Mountains
Mouth
• location	Maritsa/Evros
• coordinates	41°19′41″N 26°30′33″E / 41.32806°N 26.50917°E / 41.32806; 26.50917
Length	approx. 100 km (62 mi)
Basin size	1,618.5 km²
Basin features
Progression	Maritsa→ Aegean Sea

The Erythropotamos (Greek: Ερυθροπόταμος, meaning "red river") or Luda reka (Bulgarian: Луда река, meaning "mad river") is a river in southern Bulgaria (Haskovo Province) and northeastern Greece (Evros regional unit). Its Turkish name was Kızıldelisu. Its source is near Mega Dereio. It flows into the Maritsa (Evros) near Didymoteicho.