Easy hikes and walks around Olhalvo

The area of the springs, on the Ota River, was once a leisure area for the local population, including the local bathing area in the summer. This site remained natural for a long time after the EPAL was installed, but at a certain point, the intensification of agriculture with the use of chemical fertilizers and pesticides, intensive livestock farming, and urban sewage made the flow from upstream a polluting threat to EPAL's water intakes, and EPAL paved several dozen meters of the river course near the site where it is installed with reinforced concrete.

At this location at the top of the Serra de Montejunto, also known as "Torre" due to the various antennas that were installed there, is the Chapel of Our Lady of the Snows, which may have been built in the 13th century and remodelled and expanded during the 16th century and later. Inside, the altars covered with 17th century tiles and the altarpiece of the main altar, from the 18th century, stand out. Next to the Chapel of Our Lady of the Snows, are the ruins of what is considered to be the first Dominican Convent in Portugal, built in the 12th century and abandoned after the extinction of the religious orders, and is currently in ruins. Also nearby are the ruins of the Royal Ice Factory, classified as a National Monument. Here, in the 18th century, the Dominican monks took advantage of the climatic and geological conditions and opened large tanks connected by narrow passages, one part for the production of ice and the other for its preparation, storage and conservation. The ice was later transported to Lisbon, to supply the court and the café at Terreiro do Paço, later known as Martinho da Arcada (Fernando Pessoa's Café)

A great landmark in industrial archaeology, it is the only one of its kind in Portugal and Europe, being a symbol of medieval technology. Its construction began in 1741, and cost between 40 and 45 thousand Cruzados, a megalomaniac expense for the time, in order to satisfy the great demand for ice that existed throughout the capital. It represented a major advance in the quality and hygiene of the process used to “produce” ice, as it began to be manufactured in the factory's tanks and not harvested after the wind had piled it up, as was the case until then. (at https://www.cadavalcativa.pt)

The Nossa Senhora das Neves Chapel, located at the top of the Serra de Montejunto, has been a place of pilgrimage since the medieval period, prior to the construction of the first Dominican monastery in the 13th century.

The Ota River has its source in the Montejunto mountain range. It flows through the Ota area and empties into the Alenquer River, which in turn meets the Tagus River near Vila Nova da Rainha. At this point the river is close to the village of the same name, Ota.

Point where you can observe the region in Serra de Ota. The route is also frequented by mountain bikers, and can be covered without any major difficulties on foot.

The Serra de Montejunto Forest Watch Station can be accessed via a pastoral trail from the picnic park. It offers a beautiful panorama of the region north of the Serra.

The Serra de Montejunto picnic area is next to the Interpretation center and a little further from the campsite. Nearby there is a small bar and toilets.