One day trip to Odawara Castle in Kanagawa
If you visit Hakone and Atami, popular hot spring areas, Odawara in Kanagawa would be a good area to do a stopover. It takes only 35 mins from Tokyo Station to Odawara Station by bullet train.
Odawara castle tower was reconstructed in 1960 based on construction drawings from the Edo era and it was renovated in 2016.
The original castle was built in the mid-15th century and the Odawara-Hojo family ruled both the castle and Odawara area. It is said that Ieyasu Tokugawa referred to the design of Odawara castle when he built Edo castle, because Odawara castle was difficult to attack.
Periodically, there are special exhibitions of military commanders from warring periods. You can rent Samurai (Japanese warriors) armor, as well as Ninja and Princess costumes at Odawara Castle Information Hall.