The Upward Sun River site, or Xaasaa Na’, is a Late Pleistocene archaeological site associated with the Paleo-Arctic tradition, located in the Tanana River Valley, Alaska. Dated to around 11,500 BP, Upward Sun River is the site of the oldest human remains discovered on the American side of Beringia. The site was first discovered in 2006.

The layer with the human remains at Upward Sun River is most similar to the level 6 layer from Ushki Lake, Kamchatka. Both sites are the only Beringian burials found so far from that period.