What is a roadside memorial?
A roadside memorial is a marker that usually commemorates a site where an individual died suddenly or where an accident occurred, resulting in a fatality. The markers typically serve as a reminder to passersby of the tragedy which occurred there. Roadside memorials have been erected around the world for centuries, and their legality varies from country to country. The spread of spontaneous roadside memorials in the United States is a relatively new phenomenon. One of the first ones is belived to be a gravestone-style memorial in Ellington, Connecticut marking a child's death in 1812. Memorials do not need to be structured or permanent; these memorials often include flowers, photos, mementos, stuffed animals, balloons, or tokens of remembrance that are left at the site.
New York State will allow you to register a roadside memorial location provided you follow their guidelines. NY State law enforcement officials and DOT don’t generally prohibit or remove grieving families roadside memorials from setting up, as long as they don’t pose a major traffic disruption. More info can be found here: https://roadsidetribute.com/new-york-roadside-tributes/