Sierra mountains
- Antofagasta de la Sierra
- Castle of Carrazeda de Ansiães
- Catalan language
- High Sierra (disambiguation)
- Latin
- Mafra, Portugal
- Mountain range
- Portuguese language
- Serra (disambiguation)
- Serra da Estrela
- Serra de Montejunto Protected Landscape
- Serra do Mar
- Sierra (disambiguation)
- Sierra Ancha
- Sierra Blanca (New Mexico)
- Sierra Carapé
- Sierra Estrella
- Sierra Madre (Philippines)
- Sierra Madre Mountains (California)
- Sierra Madre Occidental
- Sierra Madre Oriental
- Sierra Madre del Sur
- Sierra Morena
- Sierra Negra
- Sierra Negra (Galápagos)
- Sierra Nevada (Spain)
- Sierra Nevada (U.S.)
- Sierra Nevada (stratovolcano)
- Sierra Nevada de Lagunas Bravas
- Sierra Nevada de Merida
- Sierra Nevada de Santa Marta
- Sierra Nevada del Cocuy
- Sierra San Pedro Mártir
- Sierra de Gata
- Sierra de Gredos
- Sierra de Guadarrama
- Sierra de Juárez
- Sierra de Mijas
- Sierra de la Demanda
- Sierra de la Ventana (mountains)
- Sierras de Córdoba
- Spanish language
- Trans-Mexican Volcanic Belt