This event is in the "Adults" group. GM Proving Ground: 100 Years of Testing 6:15pm - 7:30pm Adults Open Required This event is in the "Adults" group. Oct 14 2024 Mon GM Proving Ground: 100 Years of Testing 6:15pm - 7:30pm Adults Open Library Branch: Cromaine District Library Room: Community Room Age Group: Adults Program Type: Speaker Required Event Details: Just down the road at the Milford Proving Ground, GM automobiles have been tested for safety and performance for 100 years.