An intrusion into Kīlauea’s upper East Rift Zone during June 17–19, 2007, during the 1983–2018 Pu‘u‘ō‘ō eruption, led to widespread ground cracking and a small (~1,525 m3) eruption on the northeast flank of the Kānenuiohamo cone, about 6 km upslope from the Pu‘u‘ō‘ō vent. Transmitted and induced very-low-frequency (VLF) magnetic fields were measured with a handheld VLF receiver along transects spanning the dike trace, and zones of ground cracking related to the intrusion were mapped. This dataset records the distance between sets of nails spanning ground cracks at discrete locations in Nāpau Crater, installed in 1997 as "crack stations" to monitor change. See fig. B-1 in the associated publication for a map of crack station locations and nail configurations.