Simpson Street Subway Station and Substation #18 (IRT) National Register of Historic Places Listing

In 1904, the Bronx was still mostly fields and small villages. Then came the IRT. When the Simpson Street station opened on November 26 of that year, it acted like a starter pistol for developers. Within a decade, cheap five-story brick apartments replaced the old farms. The station itself shows off the design whims of architects Heins & LaFarge. They didn't just build a platform. They added ornamental cast-iron details, kiosk canopies, and distinct green-painted structures that still stand above Westchester Avenue. It remains a rare survivor of that first elevated expansion. Walk underneath today, and you still hear the deafening rattle of the 2 and 5 trains overhead.

But trains need juice to run. That is where Substation #18 comes in. Located at 1041 Tiffany Street, the IRT built this heavy brick structure to solve a massive engineering problem. The main Manhattan powerhouse sent out high-voltage AC. Substation #18 grabbed that 11,000-volt current. Then, massive rotary converters spun it down to the 600 volts of DC needed for the third rail. They hid this dangerous machinery behind a grand Classical Revival facade. It looked like a bank. Architects added massive arched windows that would blow outward if the equipment exploded. Smart design, really.

Today, these two sites mark the exact moment the modern Bronx was born. Before the IRT, commuting took hours. Afterward, a ride cost a nickel and took twenty minutes. This cheap fare triggered an immediate land rush. Speculators bought up potato fields. They threw up the dense brick tenements that still define the East Bronx. Listing these spots on the National Register in 2004 wasn't about nostalgia. It preserved the actual machinery that built the modern city.