Proposal 26 – Superdeep Borehole (Abandoned) and Commemorative Endless Column
Baltimore Avenue and 50th Street
In the late 70s, driven in part by Philadelphia’s provincial exceptionalism, a superdeep borehole was begun in an
unusable parcel of land at Baltimore Avenue and 50th Street. Around the time the project depleted its funding, the
drilling hit a molten sulfur deposit (which melted the drill bit) at approximately 9,583 m, and the well was plugged and
abandoned. Family members of drilling superintendent, and founder of the Philadelphia Miscellaneous Society, Dr. Parten
Demthyes, erected a monument to his endeavors over the capped shaft.