Grenora is a city in Williams County, North Dakota, United States. The population was 221 at the 2020 census. Grenora was founded in Jul…Grenora is a city in Williams County, North Dakota, United States. The population was 221 at the 2020 census. Grenora was founded in July 1916 at the terminus of a Great Northern Railway branch line that began in Stanley. The name is a portmanteau of letters in the railway's name: GREat NOrthern RAilway. The tracks were in place until 2002, when Great Northern successor BNSF Railway filed for abandonment.