During the era of the landbridge across the Bering Strait, evidence suggests that people traveled from Asia to North America by foot, becoming the first humans in the Americas and the ancestors of the Native American peoples.
That being said, even today the Bering Strait isn't terribly wide. About 50 miles at its narrowest point, roughly analogous to the English Channel and closer than Japan is to Korea. It's not a terribly hospitable environment at either end, so travel might not have been considered worth it, but given how humans tend to work their way into every nook and cranny of a landscape, it seems odd that there wasn't consistent (if infrequent) travel between Alaska and Siberia even after the landbridge disappeared.
Is there any evidence for travel, especially consistent back-and-forth travel, between Asia and North America before the modern age, but after the landbridge disappeared and foot-travel became impossible?