Table schema:
CREATE TABLE Delivery_Routes (route_name VARCHAR, route_id VARCHAR); CREATE TABLE Delivery_Route_Locations (route_id VARCHAR)

Question: Find the name of route that has the highest number of deliveries.
SQL: SELECT t1.route_name FROM Delivery_Routes AS t1 JOIN Delivery_Route_Locations AS t2 ON t1.route_id = t2.route_id GROUP BY t1.route_id ORDER BY COUNT(*) DESC LIMIT 1