Takayama is located in Gifu prefecture, north of Nagoya. The main city of the former Hida province, therefore many Japanese call Hida-Takayama instead of Takayama.
Takayama still has the well preserved historical city center and it is very popular destination for both Japanese and foreign tourists. Famous Gero onsen and UNESCO world heritage, Shirakawago are nearby.
If you visit Takayama or Hida region, you should try the Hida beef, especially Hida beef sushi. However, please expect to queue to get the sushi.
Takayama can be reached by Tokyo via Nagoya or Toyama. Take Tokaido Shinkansen to Nagoya and change to limited express Hida or take Hokuriku Shinkansen to Toyama and change to Hida. From Osaka or Kyoto, you can take Tokaido Shinkansen to Nagoya but there is a daily direct limited express Hida which connecting Osaka and Takayama. This Hida departs from Osaka station which is much convenient than Shinkansen's Shin-Osaka station.