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All Spain Las Rozas de Madrid Presa El Gasco
AO Edited

Presa El Gasco

This 18th-century project to build the world's tallest gravity dam was never completed.

Las Rozas de Madrid, Spain

Added By
Robert Entrana
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Presa El Gasco   Ceperez5
Presa El Gasco   Ceperez5
  Xavixavir / Atlas Obscura User
The wall in the south side   Luis Morato / Atlas Obscura User
South side of the dam   Luis Morato / Atlas Obscura User
El Gasco   Xavixavir / Atlas Obscura User
View from the west side   Luis Morato / Atlas Obscura User
Presa El Gasco  
Presa El Gasco  
Structure of the collapsed central part above the Guadarrama river   Luis Morato / Atlas Obscura User
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About

This impressive 173 foot (53 meters) tall structure is the most significant and intriguing remnant of an 18th-century plan gone wrong.

Presa El Gasco was designed to be the starting point for a waterway extending well over 400 miles (771 kilometers), and dropping over 2,000 feet to Lisbon. A partial collapse and financial problems put a stop to the project years after it was clear no significant shipping could have been supported with the available water supply.

Today, the area around Presa El Gasco is a natural enclave with beautiful vistas of the Sierra, a forested island among one of Madrid’s most exclusive suburbs.

A comfortable 90-minute hike will take visitors from Torrelodones to the actual site. Along the way and only partially hidden by vegetation, additional hints point to the long-gone days of construction such as small aqueducts to divert creeks, foundations of engineers’ quarters, and mounds of solidified lime. 

Related Tags

Dams Abandoned Architecture

Know Before You Go

Once at the site, exert caution. Though the dam wall is seemingly solid and sturdy, it has received no significant maintenance in decades.

Community Contributors

Added By

RobertE

Edited By

Luis Morato, jonathancarey, Xavixavir

  • Luis Morato
  • jonathancarey
  • Xavixavir

Published

June 28, 2021

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Sources
  • https://espanafascinante.com/lugar-para-visitar/que-ver-en-madrid/el-canal-del-guadarrama-cuando-intentamos-llegar-en-barco-a-madrid/
  • https://www.rutasconhistoria.es/loc/presa--del-gasco
Presa El Gasco
Las Rozas de Madrid, 28250
Spain
40.551225, -3.945093

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Photo of Las Rozas de Madrid

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