Twenty-six years before Gustave Eiffel built his famous tower in Paris, he helped construct a far more modest one in Arcachon.

The Observatoire Sainte-Cécile, completed in 1863, is a slender iron structure perched on a sandy hilltop in the Ville d'Hiver, Arcachon's quarter of ornate Belle Époque villas originally built for tuberculosis patients seeking sea air.

Designed by architect Paul Régnauld with the young Eiffel as collaborator, six railway rails form a hexagonal frame around a spiral staircase suspended by steel cables. A construction method that foreshadowed Eiffel's later, rather more celebrated work.

At 25 metres tall and roughly 72 metres above sea level, the tower was originally rigged with masts and sails as a tribute to sailing ships. Only eight visitors may climb at a time.

VoiceMap's self-guided audio tour traces the Ville d'Hiver's story from health retreat to architectural showpiece, connecting Régnauld and Eiffel's collaborations across Arcachon's bridges, parks and hilltop landmarks.