The first looping roller coaster to operate on the East Coast was the Flip Flap Railway, which opened in 1895 at Sea Lion Park on Coney Island, Brooklyn. Designed and built by Lina Beecher, this wooden coaster featured a single 25-foot circular loop. While it was a pioneering feat of engineering, it was also notoriously dangerous; because the loop was perfectly circular rather than the "teardrop" shape used in modern coasters, it subjected riders to extreme centrifugal forces estimated between 6 and 12 Gs. These intense forces frequently caused neck injuries and whiplash, leading to its closure in 1902. It was eventually succeeded by the Loop the Loop in 1901, which used an elliptical design to reduce the physical toll on passengers. Despite its short life and "neck-snapping" reputation, the Flip Flap Railway remains a landmark in amusement history as the ride that proved humans had the stomach for inversions, provided the math behind the loop's geometry was corrected for biological safety.