What do the colours mean? Doesn’t seem obvious in a phone

Poking around the map, it looks like red=towns, blue=water, grey=mountains. Not sure what yellow is.

Yellow=beach/sand?

It’s a bit odd, the markers tend to be on places/towns. But some towns that are red I know for a fact also have a beach.

Not sure what the split of colours is for.

Same on my iPad.

For some reason my brain read this as 'Map of Whales' which sounded very interesting

your title is pure book bait™ my brain read it and went ahhhhh!!WELSH!!, abandon hope ye of punny linguistic talent