This is Spotted Lake.
Due to Minerals substances in the water, the surface of the lake forms a poker dot like appearance.
Due to that, the lake has lure plenty of pokemons to its surrounding. Pokemons often benefit and grew much stronger around the area.

by the way...

there are 15 pokemons

can you spot them all??
Hahahah
HAve fun!!
Enjoy!!!

*Edit
for those who don't want spoiler, do not check the comments
if you can't find all 15 of them, check the comments for hint!!
Have fun!!

Other Wild pokemons during the camping trip

you can find the other wild pokemons here [link]