| Erythropotamos (Ερυθροπόταμος) Luda reka (Луда река) | |
|---|---|
 Luda reka in Bulgaria | |
| Native name | |
| 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 |
| 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.