Mud Run, a tributary of the Lehigh, forms the northern border of the township.

Its villages include Christmans, Christmansville, and Meckesville, and its census-designated places are Albrightsville (also in Kidder Township), Indian Mountain Lake (also in Monroe County), and Towamensing Trails.

A large portion of Hickory Run State Park is located within the township.

Penn Forest has a warm-summer humid continental climate (Dfb) and the hardiness zones are 5b and 6a.

The United States Census Bureau estimated in July 2024, the township's population increased by 6.83% to 10235.

[8] Interstate 476 (Pennsylvania Turnpike Northeast Extension) crosses Penn Forest Township north-to-south intersects with PA 903, with access at interchange number 87.

This Pennsylvania Route 903 interchange has overhead directional signage listing Jim Thorpe and Lake Harmony as end points.