Commemorative plaque to the Gate of Valnadú, Madrid

The commemorative plaque to the Gate of Valnadú stands in Madrid, on the corner of Plaza Isabel II (also known as Plaza de la Ópera), against the outer wall of the Teatro Real. It marks the spot where one of the city's medieval gates stood for five centuries before disappearing from Madrid's streetscape.

What was the Gate of Valnadú?

The Gate of Valnadú, also spelled Balnadú, was one of four main gates in Madrid's Christian defensive wall, built in the 11th–12th centuries after Alfonso VI conquered Mayrit from Muslim rule. That wall extended an earlier Arab fortification dating back to the 9th century and enclosed the core of the medieval town. The Valnadú gate served as a key passage in this ring of walls, linking the town's interior with the land sloping down toward the Manzanares river valley.

Where does the name come from?

The origin of the name is not fully settled, and historians have proposed more than one explanation. One theory traces it to the Latin "balneaduo," meaning "two baths," a reference to Roman baths said to have stood nearby. Another points to the Arabic "Bal-el-Nadar," translated as "gate of the valley," which would match the gate's position at the edge of ground descending toward the river. Locals also knew it by other names: "Puerta de las Atalayas," after the nearby Torre de los Huesos watchtower, and "Puerta del Diablo" — the Devil's Gate.

Why was it called the "Devil's Gate"?

According to local legend, a large stone with five holes resembling handprints once lay near the gate. Tradition held that this was where "the devil left his mark" — a story echoing a similar legend tied to a stone at the Alhambra in Granada. For centuries this tale fed the imagination of Madrid's residents and helped attach one of the gate's popular nicknames.

When and why did the gate disappear?

The Gate of Valnadú was torn down in 1567 on the orders of King Felipe II, who wanted the passage sealed. This was a period of intense urban transformation for Madrid, which had recently become the seat of the royal court, and the old defensive walls were losing their function to the city's expanding new districts.

What was built on the site afterward?

Stones from the demolished gate, along with material from the nearby Torre Gaona tower, were partly reused in the construction of the Teatro de los Caños del Peral, an earlier opera house that once stood on this ground before today's Teatro Real was built. Over time the area evolved into the square now known as Plaza Isabel II, right by the opera house's main entrance.

What can visitors see there today?

No trace of the gate's walls survives above ground; the only reminder of its existence is a small commemorative plaque fixed to the exterior of the building, near the Fuente de los Caños del Peral fountain. The plaque tells passersby that a gate in the town's medieval wall once stood here, demolished in the 16th century. It is a modest but telling marker of medieval history set within one of the busiest, most visited corners of central Madrid.

How do you get to the plaque?

The plaque sits at the very heart of Madrid, on Plaza Isabel II, right beside the Teatro Real — one of Europe's most important opera houses. The location pairs easily with a visit to the Palacio Real, Almudena Cathedral, or Plaza Mayor, all within easy walking distance. The area is well connected: Ópera metro station (lines 2 and 5) is literally steps from the square.

Frequently asked questions

What is the plaque at the Gate of Valnadú? It is a small commemorative plaque on Plaza Isabel II in Madrid, marking the site of a gate in the city's medieval defensive wall that stood there until 1567.

Why was the gate torn down? It was demolished in 1567 on the order of King Felipe II, as part of Madrid's urban changes after it became the seat of the royal court.

Where does the name Valnadú come from? Historians suggest two possible origins: the Latin "balneaduo" (two baths) or the Arabic "Bal-el-Nadar" (gate of the valley).

Is there anything else worth seeing nearby? Yes — the plaque stands next to the Teatro Real, and the Palacio Real, Almudena Cathedral, and Plaza Mayor are all a short walk away.