My vote is The Witcher 3 and it's expansions. Closely followed by GTA5 and Divinity OS2. 

Edit: Elden Ring is the king. Wonderful map. The only thing is, is it doesn't have a lot of activities but it's still probably the best map.

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I really love the world map of Mario Bros Wonder. Very refreshing compared to all other 2D Mario games.

Tears of the kingdom and elden ring are leagues ahead of almost everything else for me. These are the gold standard for exploration and discovery.

I forgot about Elden Ring, jesus that is one hell of a map. 

Xenoblade Chronicles X (and the series in general) has amazing environments.

Dark Souls, the vertical interconnectedness is awesome.

Elden Ring is to me peak map.

Metroid Prime, the interconnected aspect is perfection.

Yeah, From Soft are on another level for sure. Bloodborne has one hell of a map and Elden Ring too. I posted the thread and forgot about them entirely, they are probably the best at it. Elden Ring is insane. 

I'm chaning my vote to Elden Ring. TW3 is more filled but Elden Ring is immaculate.