Three concrete foot blocks for a 400’ tall, triangular lattice mast for the 1923-4 antenna extension array, assigned initially as mast 13, which collapsed, likely due to a guy wire failure, during construction. Its replacement was reassigned as mast 17. The bases are arranged in a triangle on a platform cut into the hillside. Each footpad measures 2.5m square by 0.2m high and has a central rectangular depression within which eight protruding steel bolts are set for the securing of the mast feet.

Source: Rowlands, J., Marconi's Carnarvon Station 1912-1939: a journey into early commercial wireless in north Wales' Second Edition, 2023.

RCAHMW, 2023.