North Grove is an unincorporated community and census-designated place in Harrison Township, Miami County, in the U.S. state of Indiana. North Grove was originally called "Moorefield" when it was laid out in 1854 by William North. The name was changed to "North Grove" at about the time the Pan Handle Railroad arrived in the town in 1867. A post offic…North Grove is an unincorporated community and census-designated place in Harrison Township, Miami County, in the U.S. state of Indiana. North Grove was originally called "Moorefield" when it was laid out in 1854 by William North. The name was changed to "North Grove" at about the time the Pan Handle Railroad arrived in the town in 1867. A post office was established at North Grove in 1868, and remained in operation until it was discontinued in 1934.