Nabão River

The Nabão River is a Portuguese tributary of the Zêzere River that passes through the city of Tomar. It rises in the municipality of Ansião, in the place of Olhos de Água, at an altitude of 205m and is joined, about 10 km from Tomar, by the Agroal spring, already in the municipality of Ourém. The Nabão River flows into the right bank of the Zêzere River, after a course of 61.47 km.

Its  Roman name was Nabanus.

In the Middle Ages this river was also known as Tomar or Thomar and in the upper part it was called Tomarel. Documents from the 12th century attributed to the Bishop of Lisbon, D. Gilberto, refer to a "Portus de Thomar", in defining the territorial limits of Castelo de Cera. From the context, it is understood that this reference corresponds to a crossing (Portus) of a watercourse, probably located between Formigais and Rio de Couros. In 1542 the "Tombo dos Bens e Direitos da Mesa Mestral", dated May 6, by Pedro Álvares, is perfectly clear regarding this designation of the river Tomar, still in use at the time.

Amorim Rosa speaks of historical records of major floods in 1550, in the second half of the 17th century, at the end of the 18th century, in 1852 and in 1909.

Along the course of the river, water collection and treatment equipment was installed, with a view to supplying the municipality of Tomar.

On 29 October, 1962, the largest demonstration ever took place in Tomar. At issue was the diversion of the Nabão River, at the source of Agroal, to Ourém to supply water to Fatima.

The people of Tomar got together and took to the streets to express their dissatisfaction with this government project. The demonstration, which was joined by mayors and leaders, filled Praça da República, Corredoura and other nearby streets. Faced with so many protests, the government had no choice but to drop the project.

From upstream to downstream, we find the Prado bridge, which is located before the city of Tomar, and the Flecheiro dam, already in the city.

The Nabão River, when crossing the Estremenho Limestone Massif in a deep and hollowed valley, presents the most natural part of its course and almost without marks of human presence (except for the old Paper Factory of Porto de Cavaleiros, which is abandoned) and increasingly sought after for nature tourism activities such as hiking, canoeing, caving and climbing.

The main singular points of this route are: