Heurt Fort, Military fort in Le Portel, France

Heurt Fort is a stone and concrete fort on a rocky outcrop facing Le Portel, near Boulogne-sur-Mer. Its sloping base of grey and tan blocks, quarried at Ainghem and Wimille, carries a flat upper wall of weathered timber panels with small dark openings and a thin overhanging ledge. The terrace once stood 13.50 m above the rocks and covered 175 m².

Work began on 24 May 1803 under Captain of Engineers Gouville, with plans signed by Guillaume Dode de Brunerie, later a Marshal under Louis-Philippe I. Storms and British attacks delayed completion until 16 July 1804, when the fort was to protect the southern anchorage of the Boulogne Camp flotilla. Its twin, Fort de la Crèche at Wimereux, has all but vanished.

The fort displays French military construction methods from the Napoleonic period, using cut stones from local quarries in the area.

The fort stands offshore facing Le Portel, so it can only be reached on foot across the rocks at low tide; plan the crossing around the tide tables and turn back before the water returns. Entry is through a door reached by ladder, then a circular staircase in the tower leads to the upper platform. Wear sturdy shoes, as the stone blocks and rubble are uneven and slippery.

During World War II, German forces installed anti-aircraft batteries on the fort by pouring concrete over the original structure. This concrete layer, though added for military purposes, paradoxically helped protect and preserve the older stone construction beneath it.