sidneySidney is a city in Shelby County, Ohio, United States, and its county seat. [4] The population was 20,421 at the 2020 census.It is approximately 36 miles (58 km) north of Dayton and 100 milesSituated at the shore of the Salish Sea, Sidney’s historic and vibrant downtown district is the heart of the Saanich Peninsula. Locally owned storefronts, coffee shops, eateries, and more offer