Thornapple is bounded on the north by Kent County., on the east by IrvingTwp., on the south by Yankee Springs Twp., and on the west by Allegan County.
================ The current method of numbering townships and the 36 sections within each township developed in stages, beginning with the Congressional Act of May 18, 1796. The baseline for Barry County is also its southern border, so the rows of Barry Co. townships begin with 1 N and continue northward. The prime meridian is to the east in Ingham Co., so the columns of townships begin with Range 7 W and continue westward. Michigan gazetteers show Base Line and Meridian Roads.
Sections are located as follows within each township, each being 1 square mile: