Mystery on Monster Island (1981)

A young European boy living in San Francisco is reluctant to marry his long-term girlfriend because he wants to travel around the world first. His wealthy uncle agrees to send him on a global expedition aboard his ship, but en route the boy and his travelling companion are shipwrecked on a remote island, populated by countless prehistoric creatures as well as gold-hunting bandits.
Juan Piquer Simón
Terence Stamp, Peter Cushing, Blanca Estrada, Ana Obregón, Paul Naschy, Gérard Tichy, Ian Sera, David Hatton, Gasphar Ipua, Frank Braña, Manuel Pereiro, Daniel Martín, Luis Barboo
tt0082769