This is obviously not the trailhead’s actual address; it’s someone’s house. I found this reference on PhillyFunGuide.com.

Here’s the information from the state natural resources dept. (dcnr.state.pa.us/railtrails IRON CANAL TRAIL&RegID=7, click on the “contact” link)

Organization	Phoenix Iron Canal and Trails Association
Contact	Paul Kusko
Street Address	20 Manovan Street
City	Phoenixville
State	PA
ZipCode	19460
Phone Number	(610) 933-2548