The streets of Grand Haven’s original plat were oriented to the Grand River, so that all the streets ran at an angle, different to the typical polar grid where streets run straight north and south, east and west.
Pennoyer was the first street that ran straight from west to east, and it cut through some of the original angular street pattern, which left small triangular patches of land too small to be used as building sites. These small patches of land were therefore designated as City parks.
Being so small the parks were not given official names, and thus were identified by the owners of the homes closest to them.
Johnston Park, on the corner of Pennoyer and Sheldon, was named for John & Marie Johnston, who lived at 504 Sheldon around 1908.Source: In the Path of Destiny by David Seibold