LEIRIA DISTRICT (PORTUGAL): MIRA DE AIRE NATURAL CAVES

MIRA DE AIRE

(NATURAL CAVES)

N 39º32.423' ; W 8º42.260'

Mira de Aire is a Portuguese parish in the municipality of Porto de Mós, with an area of 16.77 km² and 3,775 inhabitants. Its population density is 225.1 inhabitants/km².

In this parish, whose territory is crossed by the Natural Park of Serras de Aire e Candeeiros, are located some of the most spectacular and best preserved natural caves in Portugal, the Mira de Aire Caves, also known as Gruta dos Moinhos Velhos.

Natural patrimony.
The village of Mira de Aire is known by its inhabitants as extremely rich in terms of Natural Heritage. In addition to being part of the PNSAC (Natural Park of Serras de Aire e Candeeiros) and the place where the Mira de Aire Caves are located, the polje has several water springs that "burst" in winter, they are these:

Olho

Pena

Contenda

Regatinho

In years of heavy rains, due to the rise in the water table, floods occur in which the polje becomes a large lake. Although every year there is a strong presence of water in the polje during the winter and spring months, the last significant floods occurred in 1996 and 2001.

There are several footpaths present in the village, so it is possible to discover the urban area and, especially, the natural areas.

Patrimony
Moinhos Velhos Cave or Mira de Aire Caves
Bandstand (Mira de Aire)

CAVES OF MIRA DE AIRE

The Cave of Moinhos Velhos, part of the group of Caves of Mira de Aire, is located in Mira de Aire, in the municipality of Porto de Mós, in the district of Leiria, in Portugal.

Location

The cave is located in the Portuguese parish of Mira de Aire "in the middle of the Estremenho Limestone Massif, on the flanks of the Serra D'Aire, occupying the northern part of the Polje Mira/Minde, furrowed by national road n.º 243 that connects the junction of Torres Novas to that of S. Jorge". The access coordinates are N 39º32.423' ; W 8º42.260'.

Description

The Cave forms part of a large network of galleries, over 11 km long, and, together with the Pena Cave and the Contenda Cave, is one of the most important underground systems of the Estremenho Limestone Massif. It is characterized by the existence of two fossil paragenetic collectors, approximately decametric in diameter, with tributaries drawing a dendritic network and a set of semi-active galleries with a dendritic layout to the north and angled to the south. The fossil zone has a difference in level of 100 meters and the thickness of the intermediate zone varies between 80 meters upstream and 60 meters downstream, circulating the water through syngenetic galleries, from the north quadrant to the south quadrant, towards the outflow of Gruta da Pena .

Four stages in the evolution of the system can be defined. The first is represented by surface phreatic galleries of small diameter, the second by the paragenetic collector of the Twin Gallery, the third by the Grande Gallery and its tributaries and the last by the active and semi-active galleries of the lower floors.

An endemic cave beetle, called Trechus lunai, lives in the galleries of the Moinhos Velhos cave system and the aquatic galleries are inhabited by stigobian crustaceans, of which the most abundant is the Proasellus lusitanicus.