Paris Métro Line 1 opens

Designed by Fulgence Bienvenüe, Line 1 opened just in time for the 1900 Exposition Universelle. It featured innovative cut-and-cover construction and electric multiple-unit trains built by Thomson-Houston. The system alleviated severe traffic congestion in the growing city and became a model for subway networks worldwide. Its Art Nouveau entrances by Hector Guimard added aesthetic significance, and the line remains one of the busiest in the Paris network today.