Much of Lesotho’s cultural heritage has been studied as a result of dam developments. Where dams have been built, heritage studies have provided crucial data for improving our understanding of local archaeological sequences. Ahead of the construction of the Lesotho Highland Development Authority’s (LHDA) new Polihali Dam in Lesotho’s Mokhotlong District and following the recommendations of a heritage assessment (CES 2014), a large-scale five-year cultural heritage management program was launched in 2018 that seeks to excavate and mitigate a number of heritage sites. Here, we provide the background to one of southern Africa’s largest heritage mitigation contracts by contextualising the current research program. We then present the archaeology of Lesotho’s eastern highlands basalt region using data collected during the inception phase of this program. The findings challenge current preconceived notions about the sparsity of archaeological remains for this region.