|Area||3 km2 (1.2 sq mi)|
|Length||2.3 km (1.43 mi)|
|Width||1.1 km (0.68 mi)|
|Highest elevation||97 m (318 ft)|
Ilhéu Grande is an uninhabited island of Cape Verde. It is the largest of the Ilhéus Secos islet group, located 4 km (2 mi) west of Ilhéu de Cima, the other main islet of the group, and 7 km (4 mi) north of the island Brava. They are administratively a part of the Brava municipality.
The islet is a volcanic seamount and features rocky coastlines. It is mostly barren but has some scattered vegetation.Large colonies must have existed formerly as the island has thick layers of guano. Its length is 2.3 km (1.4 mi) from southwest to northeast and the width is approximately 1.1 km (0.7 mi) from southeast to northwest. The island is an integral nature reserve.
Its average temperature is 20 °C., its highest temperature in November is 23 °C, and the lowest temperature being 18 °C in April cooler than the neighboring island. Average yearly rainfall is 280 mm, the wettest is in September with 125 mm and the driest is in April with only a millimeter.
The island was once an agricultural land, which has been used by goat farmers and whalers in the past.
- "CV009: Ilhéus do Rombo". Sites - Important Bird Areas. BirdLife International. Retrieved 7 July 2012.
- Nature reserves of Cape Verde
- Jacques-Nicolas Bellin; Pieter de Hondt (1747). "Carte des Isles du Cap Verd = Kaart van de Eilanden van Kabo Verde" (in French).