The data contained in these files represent extracellular recordings of action potentials obtained from awake and freely-moving rats. Rats explored open arenas of different shapes during recording. The electrodes were placed in the subiculum and medial entorhinal cortex. The key raw data are positional tracking files (x,y position and head direction) at every (50Hz) sample point, and synchronised times of action potential occurrence, for each cell. In addition, the data contains rates maps, summarising mean firing rate at each position in the arena, and a series of pre-calculated scores quantifying spatial firing, for each cell.The data is contained in matlab 'table' variables. Custom code (used for the analysis described in the linked manuscript) and a guide to the data can be found at: https://github.com/WillsCacucciLab/SubDev2022/public