In the wake of the Tōkaidō Shinkansen's success, it was extended westward to connect Shin-Ōsaka with Hakata Station in Fukuoka, a project that was completed in 1975, bringing Kōbe, Himeji, Okayama and Hiroshima onto the system.
The fastest (Nozomi and Mizuho) services on the line can take passengers from Hakata to Osaka in less than two-and-a-half hours, and, with the right connections, the trip to Tokyo can be made in under six hours.
From Hakata, the Kyushu Shinkansen continues south to Kagoshima.
After ShinŌsaka, Kodama (the slower, all-station) services stop at ShinKōbe, Nishi-Akashi, Himeji, Aioi, Okayama, ShinKurashiki, Fukuyama, ShinOnomichi, Mihara, Higashi-Hiroshima, Hiroshima, ShinIwakuni, Tokuyama, ShinYamaguchi (formerly Ogori, renamed in October 2003), Asa, ShinShimonoseki and Kokura, before arriving in Hakata around five hours later.
There are usually three Nozomi services per hour (two ShinOsaka > Hakata and one ShinOsaka > Hiroshima) with most northbound trains providing a through service to the Tokaido Shinkansen.
The other super express service (the Mizuho) provides a through service to the Kyushu Shinkansen to Kagoshima with six round trips per day in mornings and evenings. Nozomi and Mizuho trains cannot be accessed by Japan Rail Pass holders, but they are covered by the JR Sanyo-Shikoku-Kyushu Pass and JR West Sanyo Pass.
A Hikari service from Tokyo continues as far as Okayama every hour, serving all stations between ShinOsaka and Okayama, while Sakura operate between ShinOsaka and Kagoshima-Chuo stopping at a few more stations than the faster services.
In practical terms, the Tokaido, Sanyo and Kyushu lines run more or less as a contiguous southbound line.
Services run between the Tokaido and Sanyo lines, so it is possible to travel from Kagoshima to Osaka, for example, though you'd need to change trains if you're going on to Tokyo.
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