View the city from Atami Castle
The Atami Castle is located at the top of a peninsula cape which overlooks the city. It is less an authentic castle (as it was reconstructed in the 1950's, and the interior features nothing authentic), and more of a tourist museum.
Access by public transport is by the Tourist "Yu-Yu" Bus, or by the Atami ropeway.
Exhibitions located within or nearby this castle are the:
Photography studio for playing dress-up in period costumes (yes, very tourist trappy, but children will love this...),
Samurai Warrior Culture Artifacts,
other traditional painting exhibition,
Ukiyoe Woodblock Shunga Gallery (minors not permitted and sorry but I'm too shy to upload the details so search keywords for yourself),
and the much gaudier Atami Secret Treasures Museum (cheers, o00o!) which is located about one minute downhill walk from this castle.