ANNAPOLIS -- Collecting old maps began as a passing interest and turned into an obsession for Owen Henderson and Russell Morrison.

Now the Eastern Shore residents are sharing that obsession with the state.

They have donated to Maryland's State Archives a collection of more than 850 maps valued at just under $1 million.

"The maps are wonderful, spectacular," State Archivist Edward Papenfuse said this week.

"It's just like a window on the past. You can see the development of the counties, the whole geographic history of the state laid out visually," he said.

The collection includes an original copy of John Smith's first map of the Chesapeake Bay and a 1635 map used to attract English settlers to Maryland.

On Monday, Morrison and Henderson received citations from Gov. William Donald Schaefer in recognition of their donation.

Morrison told Schaefer that many institutions, including the Library of Congress, wanted the collection.

But he said that because of the help he and Henderson got from Papenfuse, "there was no question where the collection was going."

He and his partner wanted the collection in Annapolis because they believed it would get more use there, he said.

They began collecting maps in earnest in 1973, Morrison said.

"You can't live on the bay . . . and not wonder every day how this wonderful place was originally settled and charted," he said. "It became an obsession. It just seemed to grow and grow."

One of the gems of the collection is the "original prospectus for colonists to come over and settle in Maryland," Morrison said. It was written in 1635.

The prospectus described Maryland, told colonists what they would get in the way of land and laid out rules for dealing with indentured servants. It included a map.

"It's one of those documents that rarely survives," Papenfuse said.

One of Morrison's favorite items is not a map, but a document relating to the Mason-Dixon line.

It is Pennsylvania's copy of the agreement between Maryland and Pennsylvania allowing surveyors to lay out the line between the two states.

The agreement was auctioned at one point by a descendant of the Penn family and eventually wound up in the hands of Morrison and Henderson. The Maryland copy was kept by the state.

"Maryland now has both sides of the agreement," Papenfuse said.

Just as important as the maps is the research on their history, he said.

Morrison estimated that 10,000 to 15,000 hours were spent researching the background of the maps.

"The state is fortunate indeed to have such a wonderful resource," Papenfuse said.