 Recent radiocarbon dating of Clovis sites has yielded ages of 11.1k to 10.7k 14C years BP (13k to 12.6k cal years BP), somewhat later than dates derived from older techniques.The re-evaluation of earlier radiocarbon dates led to the conclusion that no fewer than 11 of the 22 Clovis sites with radiocarbon dates are "problematic" and should be disregarded, including the type site in Clovis, New Mexico.Numerical dating of Clovis sites has allowed comparison of Clovis dates with dates of other archaeosites throughout the Americas, and of the opening of the ice-free corridor.