Re-imagining a lost icon of Renaissance Florence


Arts & Culture

Digital Placemaking

Woman holding up a tablet inside an exhibition gallery, a 3D church shows on the screen of the tablet.


Back in 2014 Calvium had the pleasure of partnering with professors Fabrizio Nevola and David Rosenthal of the University of Exeter to produce the original Hidden Florence app, which takes users on one of six tours through the historic city, as seen through the eyes of a contemporary citizen living during the Renaissance. In 2019, the app was extended to feature new stories and characters but perhaps more excitingly we’ve had the chance to work with the University of Exeter again to develop an entirely new Hidden Florence based app.

Hidden Florence 3D: San Pier Maggiore is a collaboration between Calvium, Professor Fabrizio Nevola at the University of Exeter, Professor Donal Cooper at the University of Cambridge, and the National Gallery, as well as our friends at Zubr.

Multiple images combined to show the Hidden Florence 3D app interface and how the AR brings the altar to life
Screenshots of Hidden Florence and Hidden Florence 3D

The app utilises AR, as well as GPS to place the user inside a reconstructed virtual model of the Church at San Pier Maggiore in Florence, which was destroyed in the 18th century. As well as recreating the Church in its native setting, the app also uses AR to recreate the building around the celebrated multi panelled altarpiece by Jacopo di Cione and Niccolò di Pietro Gerini which is situated in the National Gallery.

Being able to witness this 14th century artwork in a virtual reconstruction of its original home, allows visitors to the National Gallery to place it in its historical context and gives the artwork a new lease of life.


The Challenge

As the goals of this project weren’t commercial, the challenges associated with it were centred around working closely with the academics involved. This presented its own challenges in terms of project management, working practices and also budgeting appropriately for the work involved. 

The project is a wide ranging collaboration, between academic institutions, a part publically funded gallery and commercial entities such as Calvium and Zubr. Collaborating on research projects like this is in our DNA and exactly the kind of challenge we relish and are experienced at undertaking.

The final deliverables for the client were primarily academic and educational in nature, which is why we’ve made all the source code open source, publishing it on GitHub, along with a brief of the project, for anyone looking to take and build upon the work we’ve done.

Images of the how the church is rebuilt using AR

Hidden Florence Reimagined

The major difference with Hidden Florence 3D: San Pier Maggiore – and our primary technical challenge – was always going to be the integration of AR with the GPS in order to faithfully recreate the Church at San Pier Maggiore, both in Florence and inside the walls of the National Gallery (although the app can be used outside of these locations; at home or in the park). 

3 images combined: a black female wearing a striped dress and white trainers holds a tablet around the National Gallery and is using the Hidden Florence 3D app on the tablet. We see how by holding the tablet to the pieces of the altar hanging in the gallery, the AR builds the rest of it as it would have looked in the original church.
Hidden Florence 3D in use at the National Gallery

The first hurdle was in factoring in the complexity of building a solution that would be available to both Apple and Android devices. The scale of this challenge with the timeframe and budget available, meant we took the decision to focus our energies solely on producing a working app for Apple iOS, whilst investigating and developing methods whereby the 3D model of the Florentine Church could be made interoperable between iOS ArKit and Android’s ARCore and Unity. 

Throughout the project, we conducted workshops and experimented extensively with various presentations of the historical data in order to publish best practice guidelines for future art historians. The open source code is also now freely available to any developers involved in building intra-immersive historically accurate scaled AR experiences.

The Convergence of Research Heritage and Commercial Excellence

Not all of our work is commercial in nature, so when it comes to research projects like this we have the luxury of selecting the ones we take on, based on a set of criteria which we have developed in keeping with our founding principles. Part of the immediate appeal of the Hidden Florence 3D: San Pier Maggiore project was how it sits at the intersection of world leading academic research and public education.

This project allowed us to really get back to our roots as leaders in digital placemaking research (which date back to our founders’ work with HP Labs) and joins the growing list of research projects that we’ve worked on – including projects with the University of Brighton on NetPark, the Digital Cultures Research Centre and with igloo in Porth Teigr.


Outcome and Ongoing Collaboration

Building on the success of the first Hidden Florence app and our working relationship with Professor Fabrizio Nevola, the project undoubtedly has both an academic and public benefit. 

Without any solid commercial goals, the output of the project is based around the quality of the research and the extent to which it has helped the academics involved develop their own research methodologies. The feedback we’ve received suggests that the Hidden Florence 3D: San Pier Maggiore project has been a resounding success in this respect, with the University of Exeter now bringing in their own modellers to build, learn and further develop the technology off the back of Calvium’s source code and accompanying research notes.

Crucially, Calvium’s input into this project has been fundamental in developing a methodology that other researchers can use to grow the platform. We will also be supporting the project and the app by providing ongoing expert advice, training and guidance on user experience.

From a public perspective, Calvium are publishing the app on our own App Store account, so that it’s freely available to be downloaded and experienced by the public. This will give us and our partners much needed feedback and help to inform future development. 

Five more ‘Hidden City’ apps are now being coordinated by the University of Exeter so watch this space for more information – as and when it emerges.

Two photos taken of the Hidden Florence 3D app launch at National Gallery - we see people using an iPad and iPhone and holding them up to the pieces of the altar hanging in the gallery and can see on their devices how the AR builds the rest of the altar to show how it would have originally looked in the church

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Winner of Best Use of AR/VR in an App
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