Route 27

Route 27 is a Kanto route, and the last route to cross before reaching New Bark Town and entering the Johto region. In order to cross the route, it is necessary to walk a small distance in the Tohjo Falls. There is also a place to rest in front of the Tohjo Falls entrance.

It is to note that despite the presence of whirlpools in the waters of Route 27, they cannot be passed even with a pokemon that knows the move Whirlpool. There isn't anything blocked by the whirlpools and they appear to only be decorative.