Europe,  Spain

Barcelona: The mathematical beauty of the Sagrada Familia

I really didn’t know what to expect from the Sagrada Familia, Gaudi’s enormous basilica in Barcelona. Based on the exterior, I didn’t have very high expectations. Firstly it is a building site, with cranes and scaffolding and sheeting covering large parts of it, which is not that pretty! Secondly, to me, it is simply not a very attractive building. And I am not alone. George Orwell apparently called it “one of the most hideous buildings in the world.” If I’m honest (and I apologise to anyone who does love the exterior of this building), the Nativity Façade looks to me as though someone has hurled wet cement at it! It looks messy. It looks cluttered. And compared with the newer parts of the building it looks dirty too.

So, anyway, it was with mixed emotions that we approached the entrance below the Nativity façade to have a look inside. As we entered the basilica, our jaws dropped in unison. “Wow” was all we could utter. The beauty and serenity of the interior completely took my breath away and the building had an effect on me that I had never expected. After the rather jumbled and messy exterior, the inside is light and harmonious. The scale and colours are truly magnificent! In the central nave, the pillars rise up like tree trunks, spreading out branches at the top to form an exquisite canopy above. The size and height of it all is just astonishing. The ceiling above the nave is lit, but it also has light streaming into it in just the way that light filters though gaps and between the leaves of a forest, falling dappled on the branches and ground below.

Barcelona - Sagrada Familia Canopy ceiling

Barcelona - Sagrada Familia Ceiling main nave
The pillars seem to grow like trees, branching out to form a canopy above your head

The pillars are made of four different types of stone of different colours and strengths. Where they bear the greatest load, between the nave and transept, they are made of hard Iranian porphyry that is almost burgundy in colour, then there are dark grey basalt pillars, then granite and finally soft Montjuic stone from Barcelona itself along the lateral aisles.

Barcelona - Sagrada Familia Main nave tree-like canopy
The height and scale of the Sagrada Familia are unbelievable!

Above the side aisles, Gaudi planned galleries of seating (tribunes) that could hold two choirs. The main area can seat a choir of 1300 people, plus there is another area to hold a children’s choir of 300. How magnificent it would be to sit high up there with such a lofty view of the nave and to sing in such an incredible building!

Barcelona - Sagrada Familia Choir seating
You can just make out, on the upper level, the seating Gaudi planned for the choir

The other element of the space that is so enchanting is the movement and play of the light through the stained glass windows that flank both sides. Gaudi designed them with cooler blue tones on the side that receives the first morning sun, gradually changing to warmer tones of orange and red on the opposite side, where the afternoon sun shines through. These windows made the whole interior glow as they cast their hue across the polished floor and down the supporting pillars. It was beautiful!

Barcelona - Sagrada Familia Cool blue stained glass

Barcelona - Sagrada Familia

Barcelona - Sagrada Familia light reflections blue

Barcelona - Sagrada Familia light reflections green

Barcelona - Sagrada Familia beautiful light
The glow of the light around the basilica was beautiful
Barcelona - Sagrada Familia Light reflections inside
Just look at how the light and colours make the interior of the Sagrada Familia sing!

Outside, the building has three facades, two of which are already built.

Nativity Façade

The Nativity façade is the one part of the building that was created under Gaudi’s direct supervision, although even that wasn’t finished when he died. It is highly decorated with scenes and figures from Christ’s life and is divided into three sections that represent Hope, Charity and Faith.

Barcelona - Sagrada Familia  Nativity Facade
The Nativity facade (see what I mean about the wet cement?)

E and I climbed one of the towers in the Nativity façade, which gave us a unique view of Barcelona and the Sagrada Familia itself. You go up the tower in a small lift and then return via various different stairwells and walkways, all of which are very narrow. At one point we were able to get out onto a small ‘balcony’ but for most of the rest you are inside the tower itself or on a bridge between the towers. However you do get to see some parts of the façade very close up. We were also able to see close up some of the elements of Gaudi’s design that aren’t clearly visible from the street below and to appreciate his attention to detail. Apparently when someone asked him why he would lavish so much attention on something that no-one would see, Gaudi replied that “the angels will see them”. He also apparently said that they had to build the Nativity façade first because if they started with the more austere Passion façade, no-one would want them to continue.

Barcelona - Sagrada Familia inside Nativity tower
Looking up inside one of the towers on the Nativity facade
Barcelona - Sagrada Familia detailing
From the top of one of the Nativity towers we got a great close-up view of some features that are hard to make out from street level. Here Gaudi has used his trademark trencadis (tile shard mosaic) for the grapes and bread, representing communion
Barcelona - Sagrada Familia Nativity facade from inside tower
White doves and Cyprus tree on the Nativity facade – view from inside one of the towers
Barcelona - Sagrada Familia balcony Nativity facade
The view out from a tiny balcony on the Nativity facade
Barcelona - Sagrada Familia spiral stairway
Incredible detail: such a beautiful handrail on a stairway leading down from one of the towers of the Nativity Facade.

Passion Façade

Barcelona - Sagrada Familia Passion facade
Sagrada Familia – the Passion facade
Barcelona - Sagrada Familia Passion facade
The austere Passion facade shows the events leading up to Christ’s death

In contrast to the uplifting theme and exuberance of the Nativity Façade, Gaudi wanted the Passion façade to show Jesus’ suffering (The Passion) and the bleakness of his death. He wanted it to be cold and austere and its shape is meant to represent the strained muscles and ribs of a suffering Christ. It was completed by the sculptor Josep Maria Subirachs from Gaudi’s drawings and notes. The finished result follows Gaudi’s overall design but is altogether more angular than Gaudi’s style. However, Subirachs showed his respect for Gaudi by echoing the chimneys on Gaudi’s Casa Mila (La Pedrera) in the helmets of the soldiers and one of the figures looking on is also Gaudi himself. And if the shape of those helmets looks familiar, you should know that it Is said that George Lucas came to Barcelona and visited Casa Mila and that his visit inspired the shape of the helmets for the Storm troopers in Star Wars.

Barcelona - Sagrada Familia Passion facade details
Some of the images in the Passion facade: the figure looking on (top left) is Gaudi himself, whilst the helmets of the soldiers are meant to have been inspired by the chimneys at Casa Mila. They in turn are supposed to have inspired the storm trooper helmets in Star Wars.

Glory Façade

The Glory façade is still being built and Gaudi wanted it to be the most magnificent façade of the whole church. Like the other two facades, it will have four towers. These 12 towers (4 on each façade) will represent the twelve apostles. In fact, Gaudi planned 18 towers in all, of which only 8 are currently complete, so there is still a long way to go. As well as the 12 apostles, there will eventually be a massive central tower representing Christ and five further towers representing the Virgin Mary and the four evangelists.

Barcelona - Sagrada Familia Glory facade
Gaudi’s drawing and a photograph of his original plaster model for the Glory facade. He said “Glory is light, light gives joy and joy is the happiness of the spirit.”

As the sun moves during the day, it lights up the different facades, which is another nice touch that Gaudi planned. The morning sun shines on the Nativity façade, showing the joy of the birth of Jesus.  The midday sun will light up the monumental porch of the Glory façade and the main entrance of the church when it is finished, whilst the long shadows created by the setting sun emphasise the severe and painful images of the Passion façade.

Museu Gaudi

Also worth a visit whilst you are at the Sagrada Familia is the Museu Gaudi, which is located below ground at the side of the temple and is included in your entry ticket. It houses some interesting material about the history and construction of the building, including some of Gaudi’s original drawings and photographs of his original plaster models. It was whilst exploring this museum that I really started to understand Gaudi’s technical and mathematical genius and my appreciation of his building was taken to another level, beyond my simple reaction to its inner beauty and size.

A bit of history first…

The full name of the Sagrada Familia is ‘Temple Expiatori de la Sagrada Familia’ or Expiatory Temple of the Holy Family. Expiatory means the act of atoning for sin or wrongdoing and apparently the conservative society in Barcelona at the time wanted to build a temple as atonement for the city’s sins of modernity.

It is interesting to note that Gaudi wasn’t the original architect assigned to the job of building this temple.  The original architect was Francisco de Paula del Villar y Lozano and the first stone was laid in 1882. However, due to disagreements with the promoters, del Villar resigned after only a short time and the job of chief architect was given to Antoni Gaudi instead. At first he continued with the original plans, but after receiving a substantial anonymous donation, he proposed a new and grander design, something altogether more innovative and monumental. In 1892 work was started on the Nativity façade and by 1914 Gaudi was devoting virtually all of his time to the temple. The first tower of the Nativity façade was completed in 1925 and this was the only one that Gaudi saw finished. In June 1926 he was knocked down by a tram and died a few days later from his injuries. He is buried in the crypt of the Sagrada Familia.

Barcelona - Sagrada Familia Original models
Left: De Villar’s original gothic design for the Sagrada Familia. Right: by the time he had finished with it, Gaudi had made substantial changes. It is altogether more organic and fluid than the original

After his death, his close collaborator Domenec Sugrañes took over management of the project, continuing work on the Nativity façade, following Gaudi’s designs. However, in 1936, during the Spanish civil war, revolutionaries set fire to the crypt and destroyed the studio workshop, breaking many of Gaudi’s large scale plaster models and destroying many original plans, drawings and photographs. Since then, designers have been trying to complete the temple, remaining faithful to what survives of Gaudi’s original designs, whilst also employing new techniques and materials available today.

The church was finally consecrated by Pope Benedict XVI in 2010 and elevated to the status of a basilica.  The current date for completion is estimated to be 2026, but to be honest I have my doubts based on how much there is still to go. It would be great to come back one day and see it finished though.

Barcelona - Sagrada Familia What it will look like when finished
A model of how the Sagrada Familia will look once it is completed. Currently it is suggested that it will be finished by 2026, but I wouldn’t hold your breath!

Technical brilliance

The other aspect of the building that is explored further in the Museu Gaudi is the technical side of its design and construction.

Gaudi professed himself to be a mathematician as well as an architect and he used geometry everywhere in his designs. He wanted his building to be balanced and self-supporting: he disliked the buttresses that were used to support many gothic structures, seeing this as a defect in their design. He experimented with different solutions that would allow him to create a light brick and stone structure that could withstand the stresses of the building without the need for buttresses. One of the ways he did this was based on the theory of catenary inversion and to explore whether his designs would work, he created an inverted model of the proposed structure, using chains and bags of birdshot. The theory is that a chain suspended from two points naturally forms a curved shape known as a catenary. This catenary curve gives a perfect shape for an arch that, when turned upside down and subject to compression, can withstand the stresses from above that are equivalent to those of the chain. The bags of birdshot that he suspended from the chains corresponded to the weight of different parts of the building. The theory was that as long as the chain didn’t break, the structure would be strong enough.

Barcelona Sagrada Familia - technical specifications
Gaudi’s inverted hanging model of the nave of the Sagrada Familia (left) and technical mathematical specifications for the columns and ruled surface shapes he made use of in its construction.

Many of the shapes and structures Gaudi used in the Sagrada Familia are based on ruled surfaces – shapes such as hyperboloids, paraboloids, helicoids and ellipsoids. Ruled surfaces are mathematical shapes formed by the points or ends of a straight line when it moves or sweeps around.  For example, a cone is formed by keeping one end of a line fixed (at the top) whilst moving the other end around a circle. The explanations of some of the theory behind all of this went way beyond my understanding, but it helped me to appreciate the technical brilliance of his designs. Looking around the museum felt like I was taking a peek inside Gaudi’s head!

Practical information about visiting the Sagrada Familia

Online booking

Once again, the best way to get your tickets is to book online via the Sagrada Familia website ahead of time. As we approached the basilica there were big queues to buy tickets, but we simply walked up to the entrance, showed the tickets on my phone and were in, no waiting, no hassle at all.  I wrote more about buying tickets online in my post about first impressions and getting around Barcelona.  

You can choose a basic ticket for entrance to the basilica alone, a guided tour, or to see the basilica AND climb one of the towers. Two of our party opted to stay on terra firma, whilst two of us climbed one of the towers on the Nativity façade.

In order to purchase your tickets, you have a few choices to make:

  • What time do you want to enter?   This is fairly straightforward and you are given a 15 minute slot.
  • Do you want to go up one of the towers? You can choose between the Nativity façade or the Passion façade and this is just a matter of personal choice. We chose the Nativity façade because this is the one part of the building that was completed under Gaudi’s supervision. For the tower visit a small lift takes you up and then you walk down, along narrow stairways and ledges. Although most of these are enclosed within the tower itself, I wouldn’t recommend this for anyone afraid of heights.
  • What time do you want to visit the tower? You have to choose this in advance when you book your ticket. We allowed just over an hour between arriving at the basilica (our entry time was between 9:45am and 10am) and visiting the tower (our tower entry was at 11am) and this was plenty of time to see everything we wanted to in the basilica, to listen to the audio guide etc.  Of course, you can also continue your visit to the main basilica after you have been up the tower.
  • Do you want an audio guide? I would recommend this as there was lots of interesting information contained in it. The website says it isn’t for children, but our children listened to a lot of it and found it interesting. The basic (and cheapest) ticket doesn’t include an audio guide. You pick up your audio guide once you are through the gate, but before you enter the basilica itself.

Other things to note:

  • Try to go on a sunny day – I know this isn’t always possible, but it really does make a difference if you have the sun streaming in through the windows.
  • Children are free and so you may as well select the whole shebang including audio guide and tower visit for them and then they can do whichever parts they want to when you get there.

Finally, if you are not likely to be able to visit the Sagrada Familia in the near future and this post has whetted your appetite, there is a brilliant virtual tour you can take via the Sagrada Familia website.


  • Sue C

    Darling Sarah, could not go to sleep tonight without telling you what a wonderful account you have written about this heavenly place. Your photographs are gorgeous. We never saw it in anything like this state. I don’t think it even had a proper floor and the inside was still largely scaffolding. It’s beautiful. Thank you love. Hope you have a good week. It looks as though John will be fit enough to come with me on Tuesday and touch wood I don’t seem to have picked it up. I was speaking to Val and Haydn today and they sent their love and said how interesting they were finding your blog. Take care dear and give our love to the others. Love mum. Xx

    Sent from my iPad


    • Sarah

      Thanks Mum! It really was an incredible place and one I would definitely try to go back to in years to come to see it finished. Maybe you should plan a return visit too? Xx

  • everydayjoyfulsky

    Hi Sarah,

    I somehow landed on this site from random browsing (and clicking) around and boy am I glad to have found your blog. Your words in the Welcome page has really touched me and truly struck a chord with me. It felt like you were talking about me, about how life was just ‘happening’…

    I have been secretly wishing for the type of adventures that your family is currently embarking on, and your story is so inspiring to me that I am really going to give it some serious thought, and see if there is any possibility of making it happen for our family as well.

    Thank you so much for sharing your experiences and I look forward to following your travels on this once in a lifetime journey!


    • Sarah

      Hi Kelly

      Thank you so much for taking the time to write a comment. I am glad you are enjoying the blog. A few years ago, we were in exactly the situation you are now and I used to read (still do read) lots of travel blogs, wondering whether we would ever have the time/money/courage to take such a trip. So I am thrilled that our little blog is now inspiring someone else and I really hope you find a way to make your travel dreams come true.