In Pokémon Gold, Silver, Crystal, HeartGold, and SoulSilver, Route 19 is initially blocked off by giant boulders sent there by a volcanic eruption on Cinnabar Island. The route will be cleared as soon as the player has visited the route for the first time via Route 20, as well as having earned the Volcano Badge in Generation IV.
When Trainers first approach Route 19 from the eastern terminus, the land portion of the route is under construction for renovations. After entering Route 19 from the west, the construction will be completed.
The ocean part of the route was shrunken by approximately 50%; lastly, a gate was added between Fuchsia City and the beach.
All aspects of the route were restyled in Pokémon FireRed and LeafGreen, as the rock columns that bordered the route in the first two generations were replaced by a series of prototypical rock formations. Also, the beaches were given a rounded look to enhance their appearance.
The route was completely restyled in Pokémon HeartGold and SoulSilver. The row of rocks lining the series of cliffs has been removed and many rocks have been strewn around the beach and the sea. The beach itself is also much thinner, with the fences and rocks removed. The ocean area remains roughly the same size as in Generation II, although an island is added in the southeast corner. Like in Generation II, there is a gate separating the beach and Fuchsia City. The gate will be removed once the player reaches Route 19 from Route 20.
In the manga
Route 19 in Pokémon Adventures
In the Pokémon Adventures manga
Route 19 made an appearance in What a Dragonite, where Red was attacked by a wild Dragonite while looking for the HM03 (Surf). Although he managed to find the HM, it was broken by one of Dragonite's attacks. He was rescued from drowning by what he thought was a mermaid, but was actually Misty. Since the HM had been destroyed, Misty offered to trade Red her Gyarados in exchange for his Krabby, since Gyarados already knew Surf.