CONCARNEAU, France — In its day, the Calypso was more than an oceanographic research vessel. It was the constant companion of the famed French explorer Jacques Cousteau, as the ship and its captain logged over a million nautical miles together from the Red Sea and the Amazon to Antarctica and the Indian Ocean.

Now, all that can be seen of it is a skeletal frame, extending outside a warehouse in this small port town on the coast of Brittany in western France.

It is difficult to recognize it as the same boat that starred in award-winning films and televised adventures beginning in the mid-1950s and extending into the 1980s. Over those years, the Calypso and Mr. Cousteau turned into icons of a vibrant ecology movement, raising awareness of the wonders and fragility of the world’s oceans. Their travels brought the duo fame and made them synonymous with the romance of marine exploration, as they pursued sharks, sea sponges and shipwrecks across the globe.

Today, the Calypso rots in the warehouse where it was brought to be repaired in 2007. Stripped of the metal and wood that once encased it, weeds curling among the wooden beams of its frame, the ship is now a symbol of how Mr. Cousteau has faded in the collective memory and how despite France’s sailing tradition, neither the government nor his heirs have found a solution for its restoration.