Surf casting rods look like oversized spinning rods or bait casting rods. They are ranged from 6 to 24 feet (1.8 - 7 m) in length are able to cast the lure or bait beyond the breaking surf where fish likely pray, and strong enough to cast heavy lures or bait needed to hold the bottom in rough water. They are used in shore fishing from the beach, rocks or other shore feature or sea fishing from the shoreline. The length of the rod depends on how far and what weight of lure you want to cast, let say a 18ft or 21ft surf-casting rod will easily allow you to throw a 2- to 4-oz lure more than 200 feet.
These rods are made of a higher modulus graphite carbon manufactured in Japan, using Japanese design, engineering and technology. They are compact, provide superior portability, yet extremely flexible. Lightweight blanks are incredibly sensitive and will detect the slightest bites, and still will have enough strength to land the hardest fighters.
The advantage of long surf rod is great casting distance. Also it helps to fight the big game fish without breaking a fishing line. When a fish attacks or takes off running you can allow the fish to make very short runs to 5 or 6 ft with just the rod, not using a line. You have much more control on the fish and it allows you to use lighter line with a longer rod. With shorter rods you need to use heavier line that kills casting distance and is senseless. You can also break heavy line a lot easier with a short rod than you can with a long one.