There is a moment, in every restoration, when a wall stops being a surface and becomes a story. It happened to us on a bright morning inside one of our two historic buildings in Assisi, when the last of a modern plaster skin came away under the mason’s tools and revealed what had been hidden for generations: an arch of hand-cut stone and old brick, its joints traced in pale lime, its stones ranging from bone-white to a soft, unmistakable rose. Standing beneath it, you understand something that no guidebook can teach. In Assisi, the building is the mountain.
The Rose of Monte Subasio
Almost the entire town of Assisi is built from a single, extraordinary material: the limestone of Monte Subasio, the great massif that rises behind the city. Quarried for more than a thousand years, this stone is known simply as Pietra di Assisi, or the Rosa del Monte Subasio — the rose of Mount Subasio. It runs in colour from greyish and beige whites to a deep, warm pink, and it is the reason Assisi seems to change temperature with the light. The exterior of the Basilica of San Francesco is faced in this same stone; travellers have long noticed that it glows pink under the afternoon sun and turns almost silver-white beneath the moon.
Geologists give the rose a less romantic name — Scaglia Rossa, a fine-grained limestone laid down between the mid-Cretaceous and the Eocene, when Umbria lay beneath a warm sea. The colour comes from traces of iron worked into the rock over tens of millions of years. What matters for a restorer is that the stone is fine, dense, and beautifully workable, which is precisely why medieval masons could cut it into the crisp, alternating courses of pink and white that became a signature of Umbrian building.
This bi-chromatic masonry — deliberate bands and patterns of pink and white stone — begins to appear in the region around the tenth century and reaches its technical summit in the late 1300s and 1400s. When you find it in a wall, you are reading a date as surely as if it were carved there. Part of the pleasure, and the responsibility, of restoring a building like ours is learning to read that handwriting before deciding how to answer it.
The Craft in the Joints
A medieval wall is not merely a pile of stones. Look closely at the arch we uncovered and you see intelligence in every course: larger, squarer blocks set at the corners and the springing of the arch to carry load; smaller stones and reclaimed brick packed between them; and, binding it all, a mortar of lime. This is the quiet hero of historic building. For most of architectural history, until the early twentieth century, lime was the only binder masons used — a mix of slaked lime, sand, and water that has held Europe’s monuments together for two millennia.
Lime does something modern cement cannot. It breathes. A lime-mortared wall allows moisture that inevitably enters the masonry to evaporate back out, so that damp, salts, and frost damage are drawn away rather than trapped inside. Lime is also gently flexible, moving with the small settlements of an old structure instead of cracking against them, and it is chemically kin to the historic stone it touches. Seal a medieval wall in hard, impermeable cement — as the twentieth century too often did — and you condemn the stone behind it to slow decay. Repair it in lime and you let the building keep doing what it has always done.
This is why so much of the best conservation today is, in fact, a return to old knowledge. The revival of hot-mixed lime — quicklime slaked directly with sand, exactly as medieval masons worked it — is not nostalgia but sound building science. On our site, the decision about a single joint can take longer than laying a whole modern wall, because the question is never simply “how do we make this stand” but “how did this stand for six hundred years, and how do we honour that.”
Why We Choose to Uncover Rather Than Cover
It would be faster, and cheaper, to hide all of this behind fresh plaster and move on. We have chosen the opposite path. At Via San Francesco Assisi, the four-star superior albergo diffuso we are creating across two historic buildings a few steps from the Basilica, walls like this one will not be erased. Where a stretch of authentic medieval masonry can be safely stabilised and revealed, it will remain visible — cleaned, consolidated in lime, and lit so that guests can read the same rose-and-white handwriting we found beneath the plaster.
This is what we mean by authentic luxury. Anyone can install marble; almost no one can offer a wall that Saint Francis’s own contemporaries might have watched being built. The discolouration of pink limestone toward white or ochre over centuries is irreversible, which makes every original surface a finite, unrepeatable inheritance. Our task is not to imitate the past but to conserve the real thing and set a life of genuine comfort gently within it.
The arch beneath the plaster is now part of our daily work, and part of the reason we started writing this journal long before our doors open in 2028. If you would like to follow the restoration stone by stone — and to be among the first to stay where the mountain itself becomes a wall — we invite you to subscribe and walk this road with us.