Gruta do Lago Azul Natural Monument
| Gruta do Lago Azul Natural Monument | |
|---|---|
| Nearest city | Bonito, Mato Grosso do Sul, Brazil | 
| Coordinates | 21°08′41″S 56°35′29″W / 21.1447°S 56.5915°W | 
| Designation | Natural monument | 
| Created | 1978 | 
Gruta do Lago Azul Natural Monument (Blue Lake Cave) is a natural monument in Bonito, Mato Grosso do Sul, Brazil. It holds two caves with interesting but fragile calcareous formations, and has been listed as a protected area since 1978.