Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE branch (city VARCHAR, membership_amount VARCHAR)

### Question ###
Show all distinct city where branches with at least 100 memberships are located.

### Accurate SQL ###

SELECT DISTINCT city FROM branch WHERE membership_amount >= 100