Kuwana-jo is a castle which made use of Ibigawa river, and it was called "Ougi (fan-shaped) jo castle" from its shape.
The castle's stone walles and yagura (tower) facing the river can be seen from a ferry, so the castle was praised as a castle on Tokaido.
However, Kuwana Domain was down through Boshin war since it was on former Shogunate side. The castle was broke down after the Meiji Restoration, and some part of the stone walls was used for building Yokkaichi port.
In 1928, the former site of castle got maintenanced to be the memorial park for the 100th anniversary of Matsudaira Sadanobu. It was named Kyuka-koen park from a fan in China. The Chinese fan was called Kuwana in Edo period, and later it was called Kyuka, both names share the same kanji (Chinese characters)

Festival of Kuwana city in this month

Timeline of Kuwana-jo Castle (Kyuka Park)