This essay discusses the spatial ecology of New York City's elevated rail infrastructure. It describes how the 168 miles of elevated tracks have become deeply integrated into the city's history, culture, and daily life. While elevated highways mainly exist to move people in and out of cities, elevated rail lines embed rapid transit directly within urban landscapes. This close proximity of transportation and human habitation has created a unique urban ecosystem beneath the el tracks. The essay explores the development of New York's elevated rail system in the late 19th century, as well as public debates around issues like noise, pollution, and safety hazards. It argues the el is a quintessential New York original that remains essential to transportation around the city today.