Caban Tomorrowland is an absolute hidden gem near Tokyo, with its gorgeous views of Mount Fuji and romantic sunsets. You won't find this spot in the tourist guides!
Take the train from Shinagawa Station from to Zushi Station, its a 1 hour train ride on the Shonan-Shinjuku line and the train fare is 720 YEN, around 6 US dollars.
Upon arriving at Zushi beach, take a taxi to Caban Tomorrowland. Provide the taxi driver with the following address: 神奈川県三浦郡葉山町堀内955. Caban can be tough to get to without having a detailed address, directions and/or map.
I recommend going on a clear summer day to enjoy the sunset while having an excellent view of mount Fuji and the beach.
On the way back I recommend making a stopover in Yokohama at Cosmoworld for some fun on their Vanish roller coaster and the purikura booths.