I suggest the Tokaido Shinkansen because of it's historical significance of being the world's first dedicated high speed route, opening in 1967. It could be done in any era or multiple eras with many different models of Shinkansen to run on the route. Here's a more detailed look: What it is: The Tokaido Shinkansen is a high-speed rail line, part of the broader Shinkansen network, connecting Japan's major metropolitan areas. Key Cities: It links Tokyo, Nagoya, Kyoto, and Osaka, making it a crucial transportation artery for these regions. History: It was the world's first high-speed railway line when it opened in 1964. Speed and Efficiency: The Shinkansen travels at speeds of up to 177 miles per hour (285 km/h). Travel Time: You can travel from Tokyo to Kyoto in about 2 hours. Safety: The Shinkansen has a strong safety record, with no accidents resulting in passenger fatalities or injuries since operations began. Frequency: Trains operate frequently, with a maximum of 17 trains per hour. JR Central: The Tokaido Shinkansen is operated by JR Central. Other Shinkansen Lines: The Tokaido Shinkansen is part of a larger network that includes the Sanyo Shinkansen, which extends westward from Shin-Osaka. Train Types: Multiple train categories operate on the line, ranging from the fastest (Nozomi) to those that stop at all stations.