The milestone events will contribute to visitor spending of up to $750 million, the release stated.
This summer is the 150th anniversary of the Battle of Gettysburg, and the fall will mark the 150th anniversary of the Gettysburg Address.
There are about 3 million visitors to Adams County during a typical year, according to the release.
The visitors bureau also expects spillover of economic benefits, such as people staying in hotel rooms, into neighboring areas.
The bureau said that, according to a 2011 study, tourism supports more than 7,260 jobs in the county.
It anticipates there could be hiring spikes at area businesses, particularly for the summer.