Barragem do Rio da Mula

Barragem do Rio da Mula is a small reservoir tucked into the forested hills of the Sintra-Cascais Natural Park, offering one of the Lisbon region's most accessible and pleasant short hikes. The trail circles the calm, blue-green water on well-maintained paths through shady pine and eucalyptus woodland, with frequent glimpses of the dam wall and the surrounding hills. It is a popular spot for local families, joggers and anyone seeking a quick nature escape without leaving the Sintra area.

The reservoir was originally built for water supply, but has since become an ecological haven. Birdwatchers will find herons stalking the shallows, cormorants drying their wings on dead snags and the flash of a kingfisher darting across the water. The trail is flat and easy, making it ideal for a relaxed afternoon walk with children, followed by a picnic at one of the designated tables overlooking the lake.

Though the walk is short, the dense forest and the reservoir's tranquil atmosphere make it feel more remote than it is. The dam itself is an interesting industrial relic, and the trails continue beyond the loop into the surrounding parklands for those who wish to extend their outing. The proximity to Sintra's palaces and the Cascais coastline means it pairs perfectly with a broader day of sightseeing.