Complex sentence: It is likely that the site was known to Pre-Columbian Norse explorers from Greenland and Iceland and may be in the region of "Helluland", spoken of in the Icelandic sagas (the Greenland Saga and the Saga of Erik the Red).
Split into simpler sentences: It is likely that the site was known to Pre-Columbian Norse explorers from Greenland and Iceland. It may be in the region of "Helluland", spoken of in the Icelandic sagas (the Greenland Saga and the Saga of Erik the Red).