It could be visually beautiful, mechanically or otherwise.

I’m a visual person, so I have to go with Photosynthesis. It has an amazing table presence and the artwork is amazing. Seeing the trees slowly fill the clearing and, if the lighting is right, cast their shadows is very special.

What's your most beautiful game?

@tabletopgamesblog Isn't that football? šŸ˜›

For mass-produced boardgames I might agree with Photosynthesis.

But I'd say that I find more beauty in most handmade games than mass-produced games.

Go was already mentioned by @golgaloth but I'm also thinking of @MildaMatildaGames and also all the folk who craft their own Hnefatafl boards out of stones.

@StuffByBez @golgaloth @MildaMatildaGames Football is a beautiful game, they say, but I wouldn't know. :)

You're right. Hand-made games are often amazingly beautiful.