Write SQL query to solve given problem: In which region have the most 1-star reviews been done?. Keep the solution inside sql tag ```sql [SQL-Query] ```
SELECT T3.Region FROM reviews AS T1 INNER JOIN district AS T2 ON T1.district_id = T2.district_id INNER JOIN state AS T3 ON T2.state_abbrev = T3.StateCode WHERE T1.Stars = 1 GROUP BY T3.Region ORDER BY COUNT(T3.Region) DESC LIMIT 1