Buddy traveled the entire planet by foot, apparently.

They make no mention of Buddy ever using a boat again, but we can see from Peridot's map that North America only has two gem locations in it, and both of which are Kindergartens.

Him discovering South American gem locations? I can believe that. But, the Sea Spire? The desert pyramid? The desert pyramid is in AFRICA! The sea spire is (presumably) that structure where Russia used to be(or that one that's a slight distant away from America).

Buddy Buddwick

walked

from beach city

to africa

and freakin' europe.

Now I know he probably used a boat (even though they never mentioned it or explained how he got food during his travels), but it's still an interesting trivia fact that he walked across the entire earth in his quest for exploration. It must've took years. That diary was probably with him for at least a decade.