Regard du Trou-Morin, Historic water access structure in Le Pré-Saint-Gervais, France

The regard du Trou-Morin is a massive stone structure on avenue Édouard-Vaillant, below the sente des Cornettes in Le Pré-Saint-Gervais. It has a rectangular plan, stands 4.4 metres high and is topped by a roof of four slopes. Its walls are of rough stone, and an opening gives onto the channel that once carried spring water from the Romainville hillside toward the Saint-Lazare priory in Paris.

The water collection that led to this structure began on the hillside of Romainville in the 12th century, used by monks who sent it toward their priory and later to the Saint-Laurent fairground. The stone shelter itself dates from the 17th century, and it received official protection as a historical monument in 1899.

The word 'regard' points to the small opening through which water could be watched or reached, a detail still visible in the stone face. Local residents treat the spot as a quiet corner of daily life, often passing it on foot without stopping, while a small sign explains its former role to those who pause.

The regard stands on avenue Édouard-Vaillant, just below the sente des Cornettes, a small footpath; the south roof is best seen from that path, while the north side is viewed from the entrance of no. 49 avenue Édouard-Vaillant. The building is owned by the commune and is not open inside, so it is seen from the street.

Several sources note a spelling drift between 'Trou-Morin' and 'Trou Marin', hinting at old oral usage rather than a fixed name. Inside, ceramic pipes were later swapped for lead ones, a small material change that shows how upkeep of this rural water system continued for centuries.