The main characters in the Long Ring Long Land Arc are the Straw Hat Pirates: Monkey D. Luffy, Roronoa Zoro, Nami, Usopp, Sanji, Tony Tony Chopper, and Nico Robin; and the main antagonists are the Foxy Pirates, with their captain, Foxy the Silver Fox.
The arc takes place on Long Ring Long Land, a very long and thin island with the same characteristic of its geography in its inhabitants. The main point of this arc is the encounter of the Straw Hats with the Foxy Pirates and the Davy Back Fight that happens subsequently, which is a series of pirate games.
The Long Ring Long Land Arc revolves around something called the Davy Back Fight, an ancient pirate game where crews compete for members. Having finally arrived at Long Ring Long Land, the Straw Hats are met by the Foxy Pirates, who, in turn, challenge them to this game. In essence, the Davy Back Fight is conducted in three rounds, each of which has a different form of competition to test various strengths and teamwork.
The first round is a race around the island in boats, the second involves a ball game that is a mix between rugby and dodgeball, and the last one is a fight between Luffy and Foxy. This rest of the arc plays this out: teamwork, loyalty, and understanding what worth each member's diverse abilities bring.
Foxy, the main antagonist, is rather comical, with powers from the Noro Noro no Mi to slow down his enemies. His plans and tricks lighten up the arc compared to previous and succeeding storylines. There are also different moments of character development in the "Weakling Trio" and further depiction of Zoro-Sanji teamwork.
One of the more memorable moments of this arc is the introduction of "Afro Luffy," a comedic power-up in which Luffy dons an afro wig and believes that by doing so, he will be able to become stronger. It typifies the light, more comic nature of this arc compared to many other One Piece storylines.
The Long Ring Long Land Arc culminates when Luffy wins against Foxy to preserve the unity of his crew. In the manga, this is immediately followed by a dramatic and intense encounter with Admiral Aokiji, one of the figures in the Marine with the highest powers, in contrast with the much more lighthearted nature of the Davy Back Fight. This encounter sets a future conflict with Aokiji, raising the stakes for the Straw Hats.
It is pretty important to note that the Long Ring Long Land Arc is one of the least-liked arcs among One Piece fans, and even in its anime adaptation. The anime dragged out the arc with a large amount of fillers, which some viewers find too excessive and really hurtful to the pacing. However, the arc serves several important functions in the broader narrative of One Piece. It provides a moment of levity between the more serious Skypiea Arc and the rather intense Water 7/Enies Lobby saga that follows. It also introduces concepts and characters that become relevant in later storylines.
While this turned out to be one of the arcs with mixed reception, the Long Ring Long Land Arc just cannot be skipped in the overall One Piece narrative since it contains some canonical elements relevant to the series' continuity. The light tone and focus on pirate games in the arc give a different view of the One Piece world, varying aspects of pirate culture, and some character moments that eventually tie in with the development of the crew as a whole.
It had a recap special for this arc back in 2015, which would work as an abridged version for the storyline. The creation of the special was probably to refresh the viewers' minds on the key events of the arc and perhaps even to fix some of the pacing issues that the anime adaptation had the first time around.