two triangle metal foundations last a long time right?

[Lahar1988]

On cliffs or would I need to add a ladder or something? Triangle ones on cliffs.

[Staari™]

I usually just place stone pillars with ladders on them. Im constantly in the areas I placed them so they won't despawn. Tek lasts longer but not sure if you can place a ladder on it (i assume so) ... I don't do much tek so don't know but have seen the timers on those things are crazy. Also, if you use pillars, then rocks and trees and bushes will regrow and animals will still spawn, if you wish to destroy spawns then place foundations. Most people hate foundations tho, looks ugly against the land.

[MackMack]

You may add a fence foundation on one of the edges of your triangle foundation - just to stand on the safe side of the auto-decay.