"We're going to ring in the 250th," said Frederick County Commissioners President Mark L. Hoke.
That will be just the start, with events throughout 1998 to include historical lectures, festivals, a Civil War skirmish re-enactment, a balloon festival, an interfaith celebration and a grand parade.
Events will fit into the celebration's four themes - community, family, religion and heritage.
"We're going to have a lot of great things going on through the year - just spectacular events," said Paul Gordon, who chairs the anniversary steering committee.
Putting on a good show is important, because the events could spur interest in tourism and economic development for years to come, Gordon said.
"We want to show off Frederick County to as many people as we can," he said.
In addition, the celebration can give local residents and visitors an opportunity to rediscover the county's past, said Gordon, a former Frederick City mayor who has studied the county's history for more than 35 years.
"We enjoy Frederick County as a very special place and we need to understand the effort of the people who came before us to make it that way," he said.
Many people are aware that Frederick County was home to "The Star-Spangled Banner" composer Francis Scott Key and to former U.S. Chief Justice Roger Brooke Taney, but many stories are not as well-known, said Gordon.
For example, it was in Frederick County, not New England, that the first official act of rebellion against the British crown was committed, Gordon said.
Also, the Battle of South Mountain, fought on Sept. 14, 1862, was vital in setting the stage three days later for the Battle of Antietam, the bloodiest day in the nation's history.
And Frederick County is the only place other than Annapolis where the Maryland General Assembly has convened.
"There are many facets of Frederick County's history that many historians are not even aware of," Gordon said.