Maciço Calcário Estremenho
Olho de Mira (Mira de Aire)
- Max depth90 m
- CertificationFull cave
- Water temperature≈ 10–16 °Cestimated, no reports yet
- SpecialExperienced divers
Diving and fills
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The dive
Olho de Mira is a karst spring in Jurassic limestone on the northern edge of the Minde polje, in the Serras de Aire e Candeeiros natural park.
Profile and sections
Olho de Mira is a karst spring in Jurassic limestone on the northern edge of the Minde polje, in the Serras de Aire e Candeeiros natural park. In wet winters the water in the cave rises about 90 m and the spring overflows, together with the Regatinho spring, so that the polje between Mira de Aire and Minde floods.
The spring belongs to the Mindinho–Mira karst system: the water of the Moinhos Velhos–Pena–Contenda network, more than 11 km long, comes out here. AESDA described the cave dives and a new view of the connection between the Mindinho and Mira in its magazine Trogle 8 (2022) and in the Eurokarst proceedings.
Practical: the municipality of Porto de Mós has drawn drinking water here for more than fifty years (O Portomosense, 2019), through a well that cuts into the flooded passage.
- Depth and profile
- In winter you dive to at least 90 m of height difference and 500 m of passage (Portugal Dive, description by Rui Luís).
- Configuration
- Hard restrictions; sidemount is the obvious choice (estimate).
- DPV: Not DPV-suitable (estimate)
- Restrictions and a vertical profile: no scooter (estimate).
Who can dive where
- At least Full cave
- Configurations: Backmount / twinset / Sidemount / CCR / Small cylinders / no-mount (speleo sumps)
- Configuration unknown — research beforehand
- Goes down to 90 m (trimix or deco may be needed)
- Experienced divers only
This is how the planner decides who in your team may dive this cave. Rules your own trip adds (organizer, a mail, the AI) show with your trip.
How to get there
PNSAC authorisation required. In the rainy season the water rises about 90 m and the dive starts right at the spring; in the dry season you first have to cross a 90 m drop inside the cave to reach the water.
Around Olho de Mira (Mira de Aire)
FillsNo fill station known nearby
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