You can go to Nikko by taking the Shinkansen Bullet train and a conventional JR train. It takes about 2 hours. There is also an express train of Tobu railways which takes you directly there from Asakusa station. Nikko is registered as a national park and is especially famous for its colorful autumn leaves. 日光には東京駅から新幹線と在来線を乗り継いで約２時間で行けますし、東武鉄道を使うと浅草駅から直通の急行が出ています。日光は公立公園に指定されていて、特に秋の紅葉で有名です。