The Heal the Bay Aquarium sits beneath the Santa Monica Pier and focuses specifically on the marine environment of Santa Monica Bay. The touch tanks allow visitors to handle sea stars, hermit crabs, and urchins, and the exhibits explain the ecosystems of kelp forests and sandy-bottom habitats. The scale is small — this is not an oceanarium — but the focus is genuine and the staff are knowledgeable.
Run by the environmental organisation Heal the Bay, the aquarium emphasises the relationship between the city and the bay water that fronts it: pollution, restoration, and the marine life that has returned to the bay over decades of water quality improvement. Admission is modest ($5) and the facility is particularly good for children.