The shallow waters of Nouadhibou bay are filled with the rusting hulks of abandoned cargo ships, fishing trawlers, and the occasional warship. At low tide many lie partly on their sides on exposed sandbanks; at high tide only the superstructure shows. The effect — dozens of corroded vessels stretching to the horizon — is genuinely surreal.
Local fishermen will take you out among them in small wooden boats from the port; arrange this through your accommodation or at the harbour. There have been clean-up efforts since the 2000s and many of the most prominent wrecks have been cut up for scrap, but plenty still remain. Bring a camera and a hat.