Route 28 is a east-west route located in west Kanto and east Johto. It is the only route in Pokémon history that enters two regions, although the Johto portion of Route 28 is officially named Silver Cave. The eastern terminus is at the Pokémon League Reception Gate outside of Viridian City, Kanto, where Route 28 connects to Route 22, Route 26 and Victory Road. The western terminus is at the entrance to Mt. Silver in Johto. From the Reception Gate, Route 28 heads southwest, passing through a gap in a ledge before turning west into a strip of grass containing wild Pokémon. The narrow strip, bordered at points by a pair of small ponds, turns north after passing a small pond to its north. Route 28 forms an upside down "U" at this point, returning west at the other end. The path of the route continues through a series of intermittent grass patches before turning southwest as the route enters Johto.
The route turns west, then northwest as it approaches one of the few rural Pokémon Centers in Johto. The route continues northwest along the bank of another pond (which separates Route 28 from a small area of the route) before turning north to meet the entrance of Mt. Silver.

Mt. Silver (Japanese: シロガネやま Shirogane Mountain) is a large mountain in Johto located west of Victory Road and the Indigo Plateau. Mt. Silver can be reached from Kanto via Route 28 after receiving the sixteen gym badges of both Johto and Kanto.