I love simple little pieces like this. It's a shame you don't post here more often. ):

"How did you know they are there?"

It's helps to have program that works with indexed palettes :)

@DawnBringer Dark blue water just worked best and left a few more blue colors If I'd like to add some more details like waves.

How did you know they are there? O_O It must've my bad, probably used 90% opacity brush for mistake.

Nice & clean! You went with dark blue water for extra contrast?

There's 2 extra and dirty cyan's in the mountains of the middle top picture.  

I really like how clean the tiles are, and the colours are great as well.

I like it, simple and modern. 
And 8x8 games are enjoying to do too. 

Nice tileset.