So I want to play chess where the terrain affects movement.
For beginning sanity's sake, I think it should be basically an 8x8 board, but I was thinking each player started with 32 cards, some of which are fields (regular movement), and some of which are rocky hills (divided into 4, so they're twice as long to get through).
And it's ridiculous that castles can move at all. They're castles, fr'cryin' out loud! But could they be placed conveniently on hilltops to increase their firepower or range of vision?
Should there also be ponds, slowing knights and bishops more than they slow pawns?

i could very easily see a tile type of map that is currently used in a lot of dungeon type board games. that is arranged face down in a squarish pattern. then as your pawns/scouts get to that area you flip it. and then the terrain would affect the player/pieces differently. the pawns are light enough that they should have a massive movement ability, whereas knights and bishops would deal more damage, but have a more limited movement. and if we use your idea of castles as watch towers then maybe they could flip tiles in the vicinity before your scouts actually reached them.

just some thoughts, but we are really stretching the definition of "Chess"

Yes, well, I don't play chess much, not because I dislike the game but because I think of terrain first when I plan what to do! So, yes, this is no longer chess as such; it's a minis game played on an 8 by 8 board. I like the idea of the terrain tile flipping. I first though of using actual aerial photos, but except for Saskatchewan, they mostly aren't grid-like enough.

I kind of hate to suggest it, because they're horribly overpriced, but this is almost exactly what WotC's line of Dungeon Tiles are for. Conveniently pre-gridded, quite detailed, and double-sided. I don't think all the pieces are evenly sized (i.e. not all 1x1), but that might be more interesting, rather than less -- a 'flip' mechanic flips the whole tile, replacing the terrain in multiple nearby squares. And there are enough of them that you'd have a wide variety of terrains available.

I also sort of like the idea of building the board ahead of time -- each player places tiles in turn, filling up the 8x8 grid, vying for early terrain advantage but knowing those tiles might be flipped or replaced later.

Just as an FYI. The 'castle' is not a 'castle', it is a rook. And it doesn't represent a castle, it represents a mobile siege instrument of war. Primitive versions of the game had a chariot in that position. Later versions of the game switched that to a siege tower.

Back to your very cool suggestions for a variation on chess.

Primitive?

I did know about the castle being really a rook. I have contemplated how you move it. It should be harder to move than regular movement, but once it gets to where it's set up it should fire from there normally. Also if it is behind a hill it should have limited range.

I've gotten some printout things from Fat Dragon before and they do pretty good terrain stuff. It is just possible I can bring this travesty of an ancient and honourable game to FtC5.

That queen...