Grindstone is north of East Millinocket on Route 11 in Penobscot County.
Route 11, which follows the East Branch of the Penobscot River north to south, is the principal improved road. A short portion of the Madden Road in the south along a section of Dolby Pond is the only other improved surface.
A tiny settlement in the north of the township is near the Grindstone Falls Rest Area on Route 11. Otherwise, the balance of the land is forested with many miles of logging roads.
In August 2014 the falls looked much more challenging as a result of the low water level.