Write SQL query to solve given problem: What were the cities in which John Aalberg competed?. Keep the solution inside sql tag ```sql [SQL-Query] ```
SELECT T4.city_name FROM person AS T1 INNER JOIN games_competitor AS T2 ON T1.id = T2.person_id INNER JOIN games_city AS T3 ON T2.games_id = T3.games_id INNER JOIN city AS T4 ON T3.city_id = T4.id WHERE T1.full_name = 'John Aalberg'