This is a sort of "secret" garden located an hour outside of Tokyo about 15 minutes from Atami shinkansen station. They have an incredible amount of roses and other flowers there. They also have the biggest bonsai tree you'll ever see....
They drive you up to the top of the mountain in a little bus and then you walk down the mountain thru many different types of gardens.
If you time it in late April/early May you will see all the spring flowers blooming like crazy. Late May/June is full-blow rose garden blossoms.
If you time it right once a year they have a cos-play day where Japanese people who are into dressing up as nurses or Goldilocks or other unusual people are dressed up and wandering around the garden. It is really strange but fun to see it.
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