If you are traveling from Haverford Ave/Conestoga Road down Roberts to Ithan Creek, the cop sits about 30 feet back from the intersection of Roberts and Mill. It isn’t really a speed trap but rather a stop sign that many people roll through. The cops pull people over constantly, even if you stop and you’re not behind the actual stop sign pole (which is the imaginary line you’re supposed to stop at and then pull forward from). The cop is hidden behind a huge embankment so there’s no way to see him/her.