In 1976 Hall catalysed a landmark expedition to the Cave of the Tayos in Ecuador, involving a dozen institutions, joint special forces, and astronaut professor Neil Armstrong as Honorary President and participant.

With a scientific framework installed he later turned to Erich von Däniken's report of a metal library allegedly found in the caves by Juan Moricz in the mid-1960s, something unacceptable within an orthodox view of global history and absence of any ancient script in South America.

The British-Ecuadorian Tayos Caves expedition of 1976 was essentially a scientific extension of the 'Moricz Expedition 1969' and the 'Moricz-Hall Stones Expedition' of 1975. Below are photographs of some of the locations and participants.

The complete history about the 1976 Tayos Expedition and Metal Library can be found in the book Tayos Gold