NY's Subways Could Have Been Moving Walkways

"When Paris hosted the Exposition Universelle in 1900, it unveiled its vision for the future of transport. Below ground, the city's stylish new Metro made its debut, while above ground was something more avant garde. The trottoir roulant was a moving walkway that circled the fair in a 3-kilometre loop, its articulated wooden segments "gliding around like a wooden serpent with its tail in its mouth", according to one reporter. Nearly 7 million visitors hopped on. A few even brought folding chairs, which proved useful when one woman gave birth in transit. Her child was promptly christened Trottoir Roulant Benost. A new kind of traveller had been born..."