Arlington Springs is one of the sites where this technological revolution produced a result of continental significance: a date that pushed the story of American settlement back in ways that changed how researchers thought about the whole question.

What The Water Crossing Required — Knowledge, Not Just Boats

The requirement that the Arlington Springs individual, or whoever first reached Santarosae, crossed open water is established by geography.

What that crossing required is a more open question.

At minimum, it required watercraft of some kind — a vessel capable of supporting one or more people on the open water of the Santa Barbara Channel for the time required to complete the crossing.

The specific design and construction of that vessel is unknown and may be unknowable: organic watercraft from 13,000 years ago would not have survived in any accessible location.