“There will be a day sometime in the near future when this guide will not have to be published. That is when we as a race will have equal opportunities and privileges in the United States. It will be a great day for us to suspend this publication for then we can go wherever we please, and without embarrassment.”

That was how the authors of the “Negro Motorist Green Book” ended the introduction to their 1948 edition. In the pages that followed, they provided a rundown of hotels, guest houses, service stations, drug stores, taverns, barber shops and restaurants that were known to be safe ports of call for African American travelers. The “Green Book” listed establishments in segregationist strongholds such as Alabama and Mississippi, but its reach also extended from Connecticut to California—any place where its readers might face prejudice or danger because of their skin color. With Jim Crow still looming over much of the country, a motto on the guide’s cover also doubled as a warning: “Carry your Green Book with you—You may need it.”

First published in 1936, the Green Book was the brainchild of a Harlem-based postal carrier named Victor Hugo Green. Like most Africans Americans in the mid-20th century, Green had grown weary of the discrimination blacks faced whenever they ventured outside their neighborhoods. Rates of car ownership had exploded in the years before and after World War II, but the lure of the interstate was also fraught with risk for African Americans. “Whites Only” policies meant that black travelers often couldn’t find safe places to eat and sleep, and so-called “Sundown Towns”—municipalities that banned blacks after dark—were scattered across the country. As the foreword of the 1956 edition of the Green Book noted, “the White traveler has had no difficulty in getting accommodations, but with the Negro it has been different.”

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Inspired by earlier books published for Jewish audiences, Green developed a guide to help black Americans indulge in travel without fear. The first edition of his Green Book only covered hotels and restaurants in the New York area, but he soon expanded its scope by gathering field reports from fellow postal carriers and offering cash payments to readers who sent in useful information. By the early 1940s, the Green Book boasted thousands of establishments from across the country, all of them either black-owned or verified to be non-discriminatory. The 1949 guide encouraged hungry motorists passing through Denver to stop for a bite at the Dew Drop Inn. Those looking for a bar in the Atlanta area were told to try the Yeah Man, Sportsman’s Smoke Shop or Butler’s. In Richmond, Virginia, Rest-a-Bit was the go-to spot for a ladies’ beauty parlor.

The Green Book’s listings were organized by state and city, with the vast majority located in major metropolises such as Chicago and Detroit. More remote places had fewer options—Alaska only had a lone entry in the 1960 guide—but even in cities with no black-friendly hotels, the book often listed the addresses of home owners who were willing to rent rooms. In 1954, it suggested that visitors to tiny Roswell, New Mexico, should stay at the home of a Mrs. Mary Collins.

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The Green Book wasn’t the only handbook for black travelers—another publication called “Travelguide” was marketed with tagline “Vacation and Recreation Without Humiliation”—but it was by far the most popular. Thanks to a sponsorship deal with Standard Oil, the Green Book was available for purchase at Esso gas stations across the country. Though largely unknown to whites, it eventually sold upwards of 15,000 copies per year and was widely used by black business travelers and vacationers alike. In his memoir “A Colored Man’s Journey Through 20th Century Segregated America,” Earl Hutchinson Sr. described purchasing a copy in preparation for a road trip he and his wife took from Chicago to California. “The ‘Green Book’ was the bible of every Negro highway traveler in the 1950s and early 1960s,” he wrote. “You literally didn’t dare leave home without it.”

As its popularity grew, the Green Book expanded from a motorists’ companion to an international travel guide. Along with suggestions for the United States, later editions included information on airline and cruise ship journeys to places like Canada, Mexico, the Caribbean, Africa and Europe. “We know a number of our race who have a long standing love affair with the tempestuous city of Paris,” the 1962 Green Book noted. The guide also offered travel tips and feature articles on certain cities. The 1949 edition shined the spotlight on Robbins, Illinois, a town “owned and operated by Negroes.” In 1954, readers were encouraged to visit San Francisco, which was described as “fast becoming the focal point of the Negroes’ future.”

In offering advice to its readers, the Green Book adopted a pleasant and encouraging tone. It usually avoided discussing racism in explicit terms—one article simply noted that “the Negro travelers’ inconveniences are many”—but as the years passed it began to champion the achievements of the civil rights movement. In one of its last editions in 1963-64, it included a special “Your Rights, Briefly Speaking” feature that listed state statutes related to discrimination in travel accommodations. “The Negro is only demanding what everyone else wants,” the article stressed, “what is guaranteed all citizens by the Constitution of the United States.”

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Victor Hugo Green died in 1960 after more than two decades of publishing his travel guide. His wife Alma took over as editor and continued to release the Green Book in updated editions for a few more years, but just as Green had once hoped, the march of progress eventually helped push it toward obsolescence. In 1964, the Civil Rights Act finally banned racial segregation in restaurants, theaters, hotels, parks and other public places. Just two years later, the Green Book quietly ceased publication after nearly 30 years in print.