NATO CHAINS
1959 - 1977
A: Jan Mayen - Bo - Tarva
1961 - 1977
B: Garths Ness - Newton Point - Weybourne
1961 - 1976
C: East Blockhouse - Porspodor - Estaca de Vares
1976 - 1977
East Blockhouse - Estaca de Vares
1965 - 1977
D: Sagres Point - Porto Santo - Santa Maria - Flores