Recently been doing a practice run for my Let's Play, and come across something when covering the different Pokémon in each route.
Gold/Silver and Crystal are SATURATED with Water types (pun intended). I think most generations/games have more common typing generally, but it's helped by Old Rod no longer being a Magikarp only item.
Working it all out, the Water types available before reaching Azalea town are;
Krabby (Old Rod, Cherrygrove, didn't know that, thank you Bulbapedia).
I played Crystal a lot, in fact it's probably the one I played the most but I wasn't aware there were so many. Kind of takes the shine away from Totodile, my favourite in this generation.
I blame the Old Rod!