The Tone River runs east to west at the southern end of the town, which is located about 50 to 60 kilometers from central Tokyo.

The area was part of Shimōsa Province and was transferred to Ibaraki Prefecture in 1875 after the start of the Meiji period.

Sakai has a mayor-council form of government with a directly elected mayor and a unicameral town council of 12 members.

In terms of national politics, the town is part of Ibaraki 7th district of the lower house of the Diet of Japan.

The economy of Sakai in primarily agricultural, with rice, lettuce and cabbage as the main cash corps.