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 table_1569516_1 ( frequency__per_hour_ VARCHAR, destination VARCHAR )

### Question ###
When London Bridge is the destination, what is the frequency?

### Accurate SQL ###

SELECT frequency__per_hour_ FROM table_1569516_1 WHERE destination = "London Bridge"