In the early 1970s, Vic McGregor and Stephen Moorbath demonstrated that the Isua supracrustal belt (Greenland) and its surrounding orthogneisses formed in the Eoarchean (Moorbath et al., 1972, 1973). Fifty years later, these rocks are a key resource globally for understanding the Eoarchean Earth. This is because there is an extensive area (∼200 km2) of abundant outcrops where superimposed Neoarchean strain is modest, and Neoarchean metamorphism was only at lowest amphibolite facies; these are low tectonothermal conditions compared with other Eoarchean crustal remnants globally. Therefore, this region can provide the clearest window onto early Earth geodynamics. Within the Isua supracrustal belt there are rare areas where Eoarchean strain is also low, and these areas provide unambiguous recognition of diverse lithologies including sedimentary carbonates with the oldest proposed but contested stromatolites, pillow lavas, volcano-sedimentary lithologies and ultramafic rocks derived from