This data collection of age determination data from high latitude lake systems (50° N to 90° N, 55 sediment cores, and a total of 602 dating points) was part of the multi-core study of the LANDO approach. The term “LANDO” refers to the implementation by Pfalz et al. (2022), which stands for “Linked age and depth modeling”. We collected the data between 2018 and 2021 from either the Pangaea database, PaleoLake database, or tables within the main body or supplementary material of publications. The uploaded data collection contains links to the main data source and paper reference for the corresponding age determination dataset. The data harmonization followed the syntax and semantics proposed by Pfalz et al. (2021) (https://doi.org/10.1016/j.cageo.2021.104791) on harmonizing heterogeneous multi-proxy data. This data collection is based on drilling campaigns from 1993 to 2020.