When you come from Narita (international airport) or Tokyo to Yamanashi, it is convenient to use the railway of Chūō Line (Chūō Main Line) and highway express buses.
The Chūō Line runs between Tokyo and Nagoya, but it is much slower than Tōkaidō Shinkansen and Tōkaidō Main Line because it runs through the mountain region. Kōfu can be reached in about one hour and a half by the Limited Express "Azusa", "Super Azusa" or "Kaiji" train from Shinjuku Station, which is main connecting hub for rail traffic between central Tokyo and its western suburbs and Yamanashi & Nagano Pref. With luck, you might be able to see beautiful scenery from a train window.
There are many tunnels on the railway, some of them are more than 100 years old. Therefore, some old ones was replaced with another new ones. And now one of unused tunnels has been reborned as "Katsunuma Tunnel Wine Cave 勝沼トンネルワインカーヴ".