The data includes radiocarbon dating (¹⁴C) of peat in sediments of the first marine terrace on the Onemen Bay coast and microinclusions of organic matter direct from ice wedges, in vicinity of Anadyr town.¹⁴C ages of bulk samples of peat were obtained at the Institute for the History of material Culture, St. Petersburg (lab code Le). Radiocarbon dating of organic microinclusions from ice wedges was carried out at the Laboratory of Radiocarbon Dating and Electronic microscopy, Institute of Geography, Russian Academy of Sciences, moscow, Russia, and the Center for Applied Isotope Studies, University of Georgia, United States (direct measurements with an acceleration mass spectrometer). Radiocarbon ages were calibrated using OxCal 4.3.2 using CALIB 7.1 program with the IntCal13 calibration curve (Stuiver et al., 2019; Reimer et al., 2013).