By the turn of the 20th century, nearly 10,000 letter carriers worked in over 400 cities. The nation's population was expanding at top speed, and with it, the nation's mail volume and the need for personal mail delivery. This gallery focuses on the modern changes in mail service introduced at the beginning of the 20th century in the following sections:
- Serving the Cities: Crowded cities inspired postal officials to experiment with a variety of mail delivery systems, such as the impressive but ultimately impractical underground pneumatic tubes. Home delivery of mail began in the cities during the Civil War, when postal officials decided it was inhumane to require soldier's families to receive death notices at post office windows.
- Reaching Rural America: As rural Americans watched city residents receive free home delivery, they began to demand equal treatment. This was the start of Rural Free Delivery. Facets of Rural Free Delivery and its important and often heart warming role in the fabric of the nation is explored with photographs, mail vehicles, and a variety of rural mailboxes. A more contentious argument at the turn of the century centered around Parcel Post Service. Because Parcel Post would allow goods to be sent through the mail, individuals would have access to more merchandise, and no longer would rely on local shopkeepers. Parcel Post helped to usher in an era of consumerism by the early 20th century that foreshadowed the massive mechanization and automation of mail and the mail-order industry. Today, mail service is a vital conduit for big business.