“Appearances can be deceiving.” This proverb from Portuguese culture perfectly illustrates what is currently happening at the Teatro Nacional de São Carlos (TNSC), located in the heart of Lisbon. Anyone walking through Largo de São Carlos, in Chiado, and coming face to face with the façade of the imposing neoclassical building — constructed between 1792 and 1793 and declared a National Monument in 1996 — has no idea what is happening inside. On stage, the show is not an opera by Puccini, Verdi or Wagner, but rather a construction site. Like a classical orchestra that might be performing Mozart, dozens of workers from different specialties are, in unison, playing their instruments to give new life to one of the oldest theatres in Europe and the only lyric theatre in Portugal.
With its doors closed to the public since July 2024, the TNSC is expected to reopen in the second half of this year, following the rehabilitation and refurbishment works currently underway. idealista/news secured early access to this special season of São Carlos and visited the interior to uncover the secrets of the ongoing renovation project. Now it is time to reveal how Portugal’s “opera house” will be reborn: more modern while preserving its heritage value, so it can continue welcoming lovers of lyric art who, for centuries, have sought unique multisensory experiences there.
“In a ‘normal’ construction project we know everything that needs to be executed; here it’s the opposite. We don’t know, for example, what kind of wood existed.” Luís Lopes, site manager at Cari Construtores, the company responsible for the rehabilitation and refurbishment works at the TNSC, welcomed us and guided us through the site. Among other things, he explained that there was no climate control system and that pathways had to be created to run cables. “We have to bring it up to today’s standards,” he adds, repeatedly emphasizing that this is extremely meticulous work.
A theatre with more than two centuries of history
Walking through a labyrinth where everything is done in detail
Making use of and reusing wood and other materials
Archaeological discoveries dating back to the 1755 earthquake
An attic reminiscent of caravels… and a clock room
What works are taking place in the various spaces?
Grand Hall (where the interview took place)
Foyer
Stalls and stage
Acoustic shell
Boxes and corridor areas providing access to the boxes
Attic and clock room
A theatre with more than two centuries of history
Teatro Nacional de São Carlos
Aerial view of the Teatro Nacional de São Carlos
Credits: Gonçalo Lopes | idealista/news
First of all, some historical context about the TNSC is essential. It was designed by the architect José da Costa e Silva, built between 1792 and 1793 and inaugurated on June 30, 1793. It has been a National Monument since 1996. A neoclassical building with Italian influence, it is one of the oldest theatres in Europe and the only lyric theatre in Portugal. It was commissioned to replace the Teatro Ópera do Tejo, which was destroyed in the 1755 Earthquake — it was located in the Ribeira das Naus area.
“It stands between 19th-century buildings and is close to other listed properties. (…) Inside, spaces include: foyer, grand hall, the main elliptical auditorium with five tiers of Italian-style boxes, stage house, technical areas, dressing rooms, rehearsal rooms and administrative offices,” reads the theatre’s official website. We had the opportunity to visit some of these spaces.
Designed by architect João Mendes Ribeiro and Atelier 15, the current works fall within the second phase of the TNSC Conservation and Restoration, Rehabilitation and Modernisation project. The initiative is promoted by OPART — Organismo de Produção Artística, E.P.E., and financed by Portugal’s Recovery and Resilience Plan (PRR). The works began in September 2025, following an investment of around 17 million euros, and are expected to be completed in 2026.
This intervention (in the second phase of the overall project) focuses on the theatre’s main spaces — façades, roofs, foyer, café, ticket office, grand hall, box corridors, royal box, boxes, stage, fly tower and orchestra pit — prioritising the conservation of original materials, avoiding unnecessary replacements and extending the life cycle of building elements.
Walking through a labyrinth where everything is done in detail
Refurbishment works at the Teatro Nacional de São Carlos
One of the many corridors at the TNSC
Credits: Gonçalo Lopes | idealista/news
The idealista/news team visited the TNSC on January 15, 2026, on a grey and rainy day like many that followed. Inside, already properly equipped — wearing helmets and vests — the scene is entirely different. The smell of old wood is ever-present and more than 80 workers from various specialties are giving their best. Everything is done with precision, in detail, meticulously, with a focus on conservation and restoration. Many materials are analysed and recorded to ensure future memory. BIM technology is already being used, in favour of sustainability and seismic reinforcement.
What is the experience like? It is like walking through a labyrinth where the average person could get lost at any moment among corridors, rooms, boxes, stalls, stage… And yes, it is easy to see that this is no ordinary project — an idea frequently emphasised by the professionals (engineers, architects, etc.) accompanying the visit.
Making use of and reusing wood and other materials
Works at the Teatro Nacional de São Carlos, in Chiado
Luís Lopes, site manager at Cari Construtores
Credits: Gonçalo Lopes | idealista/news
“Each project has its own nature. Here, the materials are being discovered by us day by day; it is difficult work, but difficulty is also our challenge,” says Luís Lopes. “There is very, very old wood; we have to take it and try to reuse it. This theatre dates back to the 1790s and there is wood here from that time that is extremely important to preserve,” he adds.
But what ultimately distinguishes the TNSC from others in Portugal and worldwide? The fact that it has never burned down is in itself something special, he notes: “There is a lot of heritage and a lot of history to tell. If we go to the presidential box, we can see much of the history here, because every fabric we remove carries many stories dated to its time. Every strip of wood we remove is a story we are telling — and one we are leaving for our children and grandchildren, and so on.”
Luís Lopes also highlights the work related to the stage, which will have a slope through a motorised system — “It’s something innovative; I believe no theatre in Portugal has such a system” — and the stage machinery (the engineering applied to theatre that enables the safe and precise movement of sets, actors and lighting), considering that the TNSC will become one of the best theatres of its kind in Europe.
Archaeological discoveries dating back to the 1755 earthquake
Teatro Nacional de São Carlos under renovation
Archaeological excavations with remains dating back to the 1755 earthquake
Credits: Gonçalo Lopes | idealista/news
During the conversation, which took place in the grand hall — located above the foyer, the theatre’s main hall, where the ticket office and café are situated (both overlooking Largo de São Carlos) — Luís Lopes explained that archaeological discoveries were made which, as in any project, somewhat delayed the works.
“In the archaeological works, structures from the time of the [1755] earthquake were found, and at a certain point it was possible to see the limit of the landfill from the fire that occurred. We also have to record those structures themselves, because it is history, it is the past. Meanwhile, we have to reinvent ourselves,” he explains, noting that the archaeological findings are located beneath the stage.
Speaking of earthquakes, the works being carried out at the TNSC also aim to provide seismic reinforcement. “This building has an old wooden structure. It has undergone some structural reinforcements over the years, and all of this must be monitored. It is a combination of making use of the wooden structures, reinforcing the existing masonry walls with reinforced plaster using mesh, projected with lime-based mortars — as the building originally was — which connects with the structural reinforcement based on a metal structure. And, of course, we always have reinforced concrete structures to strengthen the foundations,” he stresses.
Very useful during this process, he assures, has been the use of BIM technology, a tool that enables 3D modelling where the installations of the entire building can be visualised.
An attic reminiscent of caravels… and a clock room
Modernisation works at the Teatro Nacional de São Carlos
In the attic, which may be open to visitors, the wood evokes caravels
Credits: Gonçalo Lopes | idealista/news
One of the highlights of the guided visit to the TNSC works is reserved for the end: the attic and the future clock room, spaces that may be open to visitors. The enormous wooden beams evoke caravels, imagines Luís Lopes, considering that they give the space rare beauty — a feeling we share, making this sensory experience unique.
“That space, and rightly so, will be prepared by the client for public visits. It’s a space that leaves us in awe. Perhaps the first time I entered this theatre, what caught my eye the most was the attic. Through a photo or video, you cannot capture the image that exists there. It’s perhaps like entering a cinema where we can see the past, the caravels,” he confides. “And next to it will be the clock room — the clock that is on the exterior façade [of the TNSC]. The works will connect these two areas. Two stairwells and two lifts will be created so people can be shown what we have there. In the past, that space was closed, and it is absolutely right to share it with everyone,” he continues.
What works are taking place in the various spaces?
We now explain, briefly and with the help of Luís Lopes and other specialists who took part in the visit, some of the works underway in this phase in several TNSC spaces.
Grand Hall (where the interview took place)
Grand Hall of the TNSC
Credits: Gonçalo Lopes | idealista/news
It will also be equipped with a sound system and air conditioning; the lighting will be corrected and the chandeliers are being restored. The most difficult aspect is always coordinating the various specialties with the existing structure, especially since below there is another important space, the foyer, which also has worked ceilings and walls. The most complicated task is always finding a path for the pipes, which are heavy. Decorative mouldings will be reintegrated and the fabrics will also be restored, as will the flooring. Essentially, everything is being recovered while maintaining its original essence.
Foyer
Foyer of the TNSC
Credits: Gonçalo Lopes | idealista/news
It is the theatre’s main hall: the ticket office is on one side and the café on the other. This is a conservation and restoration intervention; there are no specialty interventions or alterations. A team is already carrying out cleaning works, as the space has suffered wear and tear from use.
Stalls and stage
Stage of the TNSC
Credits: Gonçalo Lopes | idealista/news
The stage and stalls area will be entirely demolished and there will be a new temporary exhibition hall. The stage will have a slope through a motorised system: something innovative in Portugal, and in terms of stage mechanics it will be one of the best theatres in Europe. The proscenium arch will also be intervened; the ceiling has already been cleaned — what appears pink looks like paint, but it is canvas over the stucco structure. Everything has been restored. The clock is original. The stalls and stage are connected to a tunnel that is currently undergoing archaeological works.
Acoustic shell
Refurbishment works at the Teatro Nacional de São Carlos
Acoustic shell
Credits: Gonçalo Lopes | idealista/news
The TNSC’s acoustic shell (a removable structure, generally made of wood, placed around or beneath the orchestra/musicians to reflect sound toward the audience, increasing acoustic potential and unifying volume between stage and auditorium) has enormous heritage value and is unique in Portugal. It has an oval configuration, giving it a geometry that is difficult to reproduce, but the wooden pieces must be reused. They are being removed, restored and modelled in BIM, and will then be reassembled on site. Everything is being mapped for restoration and what exists will be preserved. The place where the acoustic shell refurbishment is being carried out has become Cari Construtores’ conservation and restoration workshop within the construction site, in what used to be the scenography office.
Boxes and corridor areas providing access to the boxes
Visit to the works underway at the Teatro Nacional de São Carlos
Interior of a theatre box, already intervened
Credits: Gonçalo Lopes | idealista/news
The corridor has been fully opened up. It was very archaic and insufficient. The exterior part of the boxes has already been intervened; now conservation and restoration of the interior is underway. There are boxes across five levels. Regarding the corridor flooring, pipe installation has already been completed, and placement is pending. In the boxes, the upholstery is entirely new, but the ceiling, skirting boards, flooring and existing wood must be removed, some restored, and then reinstalled.
Attic and clock room
Works at the Teatro Nacional de São Carlos
Attic
Credits: Gonçalo Lopes | idealista/news
The attic is a space with an architecture unlike the usual, filled with wood, reminiscent of a caravel. It may be open to visitors and used, for example, for conferences. All wood is to be preserved and maintained; anything new will serve to reinforce what exists. The clock room, next to the attic (or also within the attic), bears this name because of the clock on the exterior façade. It is a beautiful space that can function independently from the opera or performance and may host other types of events.
The final message? “I think nothing compares to this theatre; this is something else… We spend a day here, perhaps, marvelling and not noticing time passing. We’re here doing this interview and perhaps you would stay another two hours and not feel bad about being here.” Yes, Luís Lopes, that is exactly the feeling.