The Nature Conservancy, which has spent years wresting the line of 12 fragile barrier islands from private owners along the Virginia coast to create a natural preserve, was honored by the Department of Interior last week for its commitment to maintain the 33,350-acre coastal system in its natural state.

The 12 islands, owned and managed by the Arlington-based private ecology foundation, which buys land of high natural value to prevent development, represents the most extensive, least-altered barrier island and lagoon complex remaining along the Atlantic coast, Interior officials say.

The conservancy paid approximately $5 million for the islands, now known as the Virginia Coast Reserve, that stretch for 50 miles off the shores of Accomack and Northampton counties.

The islands were designated a national natural landmark by Interior Secretary Cecil B. Andrus May 14, a status that means the owners have agreed to keep the land in its natural state. The designation does not commit any federal funds to the land's preservation and is not legally binding, according to interior officials.

Paul Pritchard, of Interior's Heritage Conservation division, presented a plaque to the conservancy at its monthly meeting in Brownsville, Va., Saturday in official recognition of the group's efforts.

"This essentially draws national attention to what we consider the most important natural landmark on the East Coast," said conservancy spokesman Jack Lynn.