This route is, like most routes, very small and with one real point of interest, that being the Day Care Center. The route has two pathways to go down: the first one simply consists of side paths that have nothing on them, whereas the middle path has grass and the Day Care. You can put a single Pokémon in the Day Care and come back to it later to pick it back up. The Pokémon can level while in the Day Care (1 step = 1 Exp.) and can even learn new moves. They will not evolve while in the Day Care, though. Later down the route is an underground tunnel to the south and a gate that also leads to the south. The underground tunnel is a quick way to get to Route 6 and, in turn, Vermillion City. You can also trade a Nidoran♂ for a Nidoran♀ (Red, Blue and FireRed), Cubone for a Machoke (Yellow), or a Nidoran♀ for a Nidoran♂(LeafGreen) in the underground tunnel. The gate to the south has a thirsty guard in it who will stop you from entering Saffron City until you give one of the guards tea (FR/LG) or Fresh Water (R/B/Y).
Red: Pidgey (35%), Oddish (40%) and Mankey (25%)
Blue: Pidgey (35%), Meowth (25%) and Bellsprout (40%)
Yellow: Pidgey (45%), Pidgeotto (5%), Rattata (25%), Jigglypuff (10%) and Abra (15%)
FireRed: Pidgey (40%), Meowth (35%), Oddish (25%)
LeafGreen: Pidgey (40%), Meowth (35%), Bellsprout (25%)