According to the United States Census Bureau, the affluent borough had a total area of 11.7 square miles (30 km2), all of it land. Its average elevation is 1,197 feet (365 m) above sea level. Bethel Park lies at the margin between the Pittsburgh Low Plateau and Waynesburg Hills Sections of the Allegheny Plateau physiographic province. The area is characterized as a maturely dissected region where the ephemeral minor tributaries converge into the tributaries of principal streams.
The highest point in Bethel Park is Rocky Ridge, in the southwestern portion of the municipality, 1,370 feet (420 m), and the lowest point is at the intersection of the Piney Fork and Alsip Run creeks, 980 feet (300 m), in the southeast corner of the municipality.
All information about Hoffman Estates courtesy of Wikipedia.