Free Walking Sightseeing Tour #1 in Cascais e Estoril, Portugal

Boca do Inferno is a chasm located in the seaside cliffs close to the Portuguese city of Cascais, in the District of Lisbon. The seawater has access to the deep bottom of the chasm and vigorously strikes its rocky walls, making it a popular tourist attraction. The cave was the first to be depicted in moving pictures, in the 1896 British film A Sea Cave Near Lisbon, which shows waves breaking at the mouth of the cave.

Wikipedia: Boca do Inferno (EN)

The King D. Carlos Sea Museum is a Maritime Museum in the fishing town of Cascais, Lisbon District, in Portugal. It was inaugurated in 1992.

Wikipedia: Museum of the Sea, Cascais (EN)

The Cascais Cultural Centre is situated close to the Citadel of Cascais in the municipality of Cascais in the Lisbon district of Portugal. It consists of several exhibition spaces, a recital hall and a restaurant. Opened in May 2000, parts of the building date back to the end of the 16th century, when it was constructed as a Carmelite monastery. The Centre is managed by the Dom Luís I Foundation.

Wikipedia: Cascais Cultural Centre (EN)

The Fortress of Nossa Senhora da Luz de Cascais is located in a dominant position in the Cove of the same name, on the right bank of the Tagus River, in the village, parish and municipality of Cascais, Lisbon district, in Portugal.

Wikipedia: Forte de Nossa Senhora da Luz de Cascais (PT), Heritage Website Sipa, Heritage Website

The Cascais tide gauge was the first tide gauge installed in Portugal and dates back to 1882. It is situated in Cascais Municipality, Lisbon District. It was one of the first systems of sea-level data collection installed on the coast of Europe and is still in use.

Wikipedia: Cascais tide gauge (EN), Heritage Website Sipa, Heritage Website