The dataset contains borehole-GPR (ground penetrating radar) data from a shallow quaternary glacial aquifer at the test site "TestUM" in Wittstock/Dosse (Germany). At the test site a geological latent heat storage concept was tested while freezing and thawing a subsurface volume in a controlled manner. Therefore, 16 heat exchanger probes, 18 m deep each, are installed in a 1 m x 1 m-grid. 22 2-inch wells and eight multilevel wells are installed to provide direct access to the aquifer for groundwater sampling and borehole measurements. The borehole deviation of the 2-inch monitoring wells was measured using a deviation probe (DevProbe1, Geotomographie, Neuwied, Germany). Readings of tilt and direction were taken for every borehole, allowing calculation of the well path in the subsurface. Reflection and crosshole borehole GPR measurements were performed before and during two freezing cycles. The data were collected from November 2022 to December 2023. The borehole GPR measurements were performed in the 2-inch monitoring wells. To record the data, we used a GSSI SIR 4000 (GSSI Geophysical Survey Systems, Inc., Nashua, USA) and one (reflection measurements) or two (crosshole measurements) Tubewave-100 antennas (Radarteam Sweden AB, Boden, Sweden). For reflection measurements, an antenna was used that served as both transmitter and receiver. It was lowered into a borehole, and measurements were taken every 0.25 meters starting at a maximum of 16.75 m up to 0.25 m depth. The crosshole measurements were realized as zero offset profiles with two antennas. One served as a transmitter and one as a receiver. They were placed in two boreholes and lowered simultaneously, with measurements taken every 0.25 m at the same depth starting at a maximum of 16.75 m up to 0.25 m depth.The naming of the 2-inch wells was adjusted according to the groundwater flow direction from northeast to southwest. Wells located upstream of the freezing area start with the letter U, central wells with the letter C, and downstream wells with the letter D. For the reflection measurements, four boreholes were measured upstream (U03, U04, U05, U06), two in the center (C04, C05), and five downstream (D02, D04, D05, D06, D08). For crosshole, various measurements were chosen to characterize the subsurface before freezing, including combinations of upstream-downstream, upstream-center, center-center, and center-downstream. During the freezing phase, the crosshole measurements were conducted using combinations of upstream-upstream, upstream-downstream, center-center, and downstream-downstream.