Justo Gallego Martínez was handed a plot of land in Madrid by his family 60 years ago.

Soaring 115 feet above a nondescript suburb, its Byzantine towers, turrets, Mozarabic arch and cupola have turned a building with no planning permission and no architect’s plans into Spain’s unlikeliest tourist attraction.

But it is also an orphan. Gallego died on Sunday, aged 96, his life’s work incomplete, its future in limbo. His dying wish was to be buried in the crypt, just as Antoni Gaudí reposes in Barcelona’s Sagrada Familia.

Joke comparisons have long been drawn between Gallego and Antoni Gaudí who designed Barcelona’s Sagrada Familia, to the extent that the local council named the street that runs alongside Gallego’s temple after the better-known Catalan architect.

Gallego began building his cathedral as an homage to Our Lady of the Pillar the Blessed Virgin Mary after he survived a bout of tuberculosis. He was dismissed at first as a crank who was asked to leave his monastery, but obscurity gradually gave way to admiration as his vision took shape from discarded construction materials.

A thousand plastic tubs donated by the local baker became moulds for the vaulted ceilings. The cathedral’s pillars were built from stacked oil drums. Its two thousand stained-glass windows were painstakingly created from fragments glued together.

Covering more than 50,000 sq ft, the building boasts two cloisters above the crypt, 12 towers and 28 cupolas, of which the main dome was inspired by the Vatican. For its grand entrance hall, Gallego looked to the White House in Washington.

While faithful Christians have drawn inspiration from his tenacity and commitment, the secular praise him as a pioneer of the recycling movement. Yet neither the council nor the Catholic Church have offered to take responsibility for his construction.

Sensing that his time was drawing near, Gallego donated the unfinished cathedral to Messengers of Peace, an non-governmental organisation that works with homeless people, earlier this year. Against all odds, a survey performed by Calter, an engineering firm, declared it structurally sound.

The company, which worked on Real Madrid’s Santiago Bernabéu stadium, told The Times: “It is incredible that a cathedral of this scale was built without blueprints nor an overall design, and that this was done by a single individual.”