Clymer is a borough in Indiana County, Pennsylvania, United States.

Most of Clymer's family died in a tragic sea accident in 1878, which made national news and inspired the name.

[4] According to the United States Census Bureau, the borough has a total area of 0.6 square miles (1.6 km2), all land.

On 26 August 1926, forty-four people were killed in a coal mine explosion in Clymer.

There were 734 housing units at an average density of 1,236.8 per square mile (477.5/km2).