Task: Text to Code
Input (English): Step 1: For each row in circuits table, find the corresponding rows in races table.
Step 2: find the number of rows of each value of country in the results of step 1.
Step 3: find races's url, country of step 1 results with largest value in the results of step 2
Output (English): SELECT T2.url , T1.country FROM circuits AS T1 JOIN races AS T2 ON T1.circuitId = T2.circuitId GROUP BY T1.country ORDER BY Count ( * ) Desc LIMIT 1