Koga is a city located in Ibaraki, Japan. The city has its origins in the Tokugawa period when a castle was built in the 16th century at the river crossing point and a town sprang up around it. The site of the castle is still visible near Koga 1st elementary school. The modern city was founded on August 1, 1950. It has many old shrines like Suzume jinja. Some are dedicated to O-inari and some old temples like Hase Kannon. Sogo Koen Park near the Watarase river is a lovely place for all the family and was formally a summer palace for a local shogun.It has two restored 17th century farmhouses like Old Nakayama house.Takami Senseki house/museum near the history museum is also Edo period. There is a literary museum also located in the city.