Originally named Tower Rock, May Rock is the largest outcropping of quartz along the Mother Lode. This 82 foot high formation contains no gold ore. Most gold ore within quartz is at greater depths in the earth.
It was part of Colonel John C. Fremont's1847 "Las Mariposas" 44,000 acre land grant and later owned by Louis Trabucco.
To celebrate May Day, people came from Bagby, Bear Valley, Elkhorn, Hornitos Mariposa, Quartzburg, and Princeton.
It became the central gathering place on May Day for picnics, races, music and a May Pole dance.
Jessie Fremont was an early organizer of these events and bestowed the name May Rock, in remembrance of the May Day picnic here.
May Rock is currently owned by Robert Bondshu, a descendant of the pioneer Bondshu, Hope, Halstead, and McGregor families of Mariposa County.