Maryland

1909 - 1929 1911 through 1915: Porcelain

1930 - 1950

1950 - 1969

Assateague Island is a barrier island off the coast of Maryland and Virginia. The northern two thirds consist of the Assateague State Park and Assateague Island National Seashore in Maryland and the southern third, Chincoteague National Wildlife Refuge, is part of Virginia. There are no residents.
Permit plates were issued to jeeps and other all-terrain vehicles, allowing visitors to drive, camp and fish on the beach.

1966 - 1967: ABBA (Assateague Beach Buggy Association) and a serial number
Since 1968: AMSA (Assateague Mobile Sportsfishermen's Assocation) and a serial number
1986: Undated plate renewed in 1987 with a sticker
1988: The lower text changed to MD./VA. (Maryland/Virginia)
1992 - 1999: Yellow on black plate renewed annually by stickers
2000 - today (?: Blue on white plate renewed annually by stickers

Source: (7)