The Niagara Baths, Madrid's first indoor swimming pool
EL RIGOR · 9 de agosto de 2026, 21:51 · 2 min read
Cross-checked in sources from El Mundo
On the bustling Cuesta de San Vicente, beneath the foundations of the Hotel Príncipe Pío, lie the remains of the Baños del Niágara, which opened in the summer of 1879. This complex, which transformed hygiene and sporting habits in Madrid, was the first large public swimming pool in the city and, decades later, became the country's first heated and covered pool.
The Baños del Niágara began its life as an urban sanatorium, conceived by entrepreneur Vito Montaner. The complex included medical consultations, a pharmacy, and individual treatment rooms, featuring a large outdoor pool measuring 27 metres in length, considered the first swimming pool in Madrid. Its initial purpose was to offer therapeutic treatments using cold water jets, but it soon evolved into a recreational space.
In the 1910s, entrepreneur Santiago Domínguez transformed the site into a recreation park, adding a summer cinema that screened international silent films. According to contemporary press reports, Madrileños flocked in droves during July and August nights for refreshing swims followed by open-air movies.
However, the Niágara reached its zenith in the early 1930s when it became the first heated and covered swimming pool in Madrid. This transformation was driven by the Canoe Natación Club, which needed a space to train during winter. The engineering feat involved reducing the original pool from 27 to 25 metres to comply with international sports regulations and completely covering it to protect it from frost. Additionally, a coal-fired boiler was installed to maintain a constant water temperature.
Building a heated and covered pool in the middle of winter was an innovation that anticipated future needs of athletes and sports enthusiasts.
Today, although the Baños del Niágara remain hidden under the foundations of the Hotel Príncipe Pío, their legacy endures in the collective memory of Madrid. The Niágara not only changed hygiene and sporting habits in the city but also left an indelible mark on Madrid's culture. Its history is a testament to the constant change and adaptability of the city over time.
Piece prepared by the newsroom from cross-checked sources in several countries.