Found and studied by archaeologists from the British Museum, the footprints are estimated to be anywhere from 780,000 to one million years old.
The footprints were discovered pressed into estuary mudflats along the coast of Happisburgh, England, a small village in low-lying Norfolk county. Happisburgh had previously been identified as one of the earliest sites of human activity outside of Africa, when ancient flint tools were discovered there in 2010.
The newly-discovered footprints became visible as a result of coastal erosion, the mudflats revealed, as the beach's sand became washed away by waves and current.
First spotted in May 2013, scientists had to act quickly to document the prints before time and stormy seas washed away human history.
Based on detailed analysis of the footprints, scientists believe impressions were left by a party of five -- men, women and children -- as they strolled the riverbanks. Although archaeologists have no human remains on which to conduct DNA testing, they estimate the prints were left by Homo antecessor, or "Pioneer Man," a species with a slightly smaller brain than modern humans, but one that walked upright on two feet.
"We actually know very little else about the people who left these prints," explained researcher Nicholas Ashton, "but from the plant and animal remains at Happisburgh we know that they were able to survive winters colder than today."
"We’re still asking questions of whether they had clothing and shelter or controlled the use of fire," Ashton added.