A half-ruined church, and its separate bell towers which will soon be swept away by the waves:sculptures eaten away by time, crumbling columns, abandoned houses… the album that Pietre Wiersma glances through – more than 70 photos, carefully dated and numbered – is the only evidence of his oeuvre: untiringly, for the last 10 years, he builds sand castles on the beaches of the Netherlands

A slim silhouette, a face devoured by beard, the man who greets me does not look his 39 years. Intimidated as I am myself, he runs to the kitchen to make coffee. That lets me look about:: a banal repro of Jerome Bosch stuck above the entrance: above his bed, a framed photo; a worn carpet. I imagined a crazier universe, not this poor student dorm.

At 8, when his friends had long left the sandbox, Wiersma already spent obssesive care on the castles he built near the family home. “Very simple” constructions, angles squared off with a penknife or a bit of wood. “Forms one obtains working only with the hands are too rough”

He does not evince happy childhood memories.”I was very much alone” Others “were passionate about soccer, I about design.”

He still has a yellowed photo of one of his first churches, taken by a classmate when he was 13. “It was more than friendship”, he murmurs under his breath. “I truly loved him. Like me, he was interested in sciences and in architecture, but he changed schools and we lost sight of one another.” By chance, they met again two years ago. Wiersma invited him to an exhibition. Now a doctor of psychology, his former friend was surprised to see that he could still “amuse himself” with sand castles. He had completely forgotten them and no longer remembered the photos he had taken!

No longer able to work at the race track, which had allowed him the habitual construction of his edifices, Wiersma had not returned to his chateaux for 10 years. From ’62 to ’72 by his own reckoning, he had other ideas in mind. “Love seemed to me more important” After studies in engineering, he joined the Monumentzorg, charged with safeguarding and restoring buildings classed as monuments.

One fine day, however, his former passion repossessed him. As he walked along a beach near Haarlem, his attention was caught by a young man who was trying “awkwardly” to build a fortified chateau; he proposed to give him a hand. “The sand was much easier to work than I believed.” It was wetter, firmer than that of the racecourse he had always known.

For eight years now, he spends all his summer week-ends beside the sea. His compositions, more and more daring, take him whole days to construct. “For a bell tower, I need two hours, easily. One must pile up the sand shaft by shaft, and mold it firmly so that it will hold. The slimmer the shafts, the less the risk of crumbling”

Sometimes, he goes so far as to sleep near his works and to finish them next day, adding here a new tower, there a contrefort. He sprays them with salt water; the crust thus formed protects them. “If it’s too dry, it will crumble. The salt absorbs humidity from the night air.”

When he thinks the whole finished, and only then, he takes a few photos. Waiting patiently in the open window for the precise moment: when the sun cuts the shadows, when rays of light fall exactly as he has planned.

These monuments are often only about 40 centimetres tall – the biggest he had ever built was no more than one metre forty but, deliberately, the photos conceal the scale.

Outside of the Hague cathedral – which he amused himself by copying, Pieter Wiersma prefers always to improvise. In the train which takes him each Saturday toward the sea, he may scratch out a sketch, tiny bits of paper that he jealously conserves. His inspiration is often religious, referring to Viollet le Duc or Antonio Gaudi. The Spanish architect has influenced him a lot: one finds the same details borrowed from medieval art, the same Byzantine arabesques. Just as Ferdinand Cheval immortalized his wheelbarrow, which helped him carry the stones of his ideal Palace, Wiersma rendered homage to his shoes, sculpting them twice as big as they really are.

He preferred this day to await solitude, “in order to work in peace” . People’s reactions are so unpredictable…. “Generally, they don’t stop, don’t say a word, they just think me bizarre.” But as soon as he turns his back, some hasten to destroy everything. Which makes him furious “above all if I have not had time to take photos". If he can, he returns for a few days, fascinated by the process as his buildings slowly fall into ruin.

Many of his works were included in an exhibition of fantastic architecture, presented in Amsterdam and Haarlem. Last year, he was invited to the Venice Biennale but he is hesitant to renew his museum experience. His works of art, according to him, are made for the wind…they lose their beauty in an enclosed space with artificial light.

Peter Wiersma would like to give more time to his chateaux but full time work prevents this. Cramped in an office waiting for summer - the only time he can work without freezing - no longer amuses him. So he looks forward to the day when he can leave the Monumentenzorg,. He has already 60,000 florins saved. Soon he will be able to realize his dream : to travel far away - to Surinam or Indonesia , where the sand is glistening white and the beaches are always sunny.