I parked in Brandon town, just in case going to the visitor centre left me returning to the car after it closed. I walked through some residential streets down to the forest, and followed the path to the brandon visitor centre. There's a little pond, and several play areas, and it's quite foresty while also being well sign-posted. You can wander round near the visitor centre and see lots of people, or go not far away and find it almost deserted.
I poked around the landmarks for a little, and walked past some artwork. I'm a sucker for anything named "X and rust" for some reason. And a mausoleum the size (and shape) of a modest house.
Then I went off down one of the trails, found a sunny open area, took my shoes off, and read and spodded for a while.
Then I felt like wandering, and with a combination of google maps and osm, I headed along whatever paths went east, to visit the bigger visitor centre, High Lodge. I'd forgotten that was the Go Ape place until I was halfway there, and also ran mountain bike trails of various difficulty round the forest.
Then I curved back round to the town and home. I went home via a pokemon gym at a church in a tiny village, just in case it lasted long enough to get another gym badge. It got halfway to silver but not more.
Thetford is very distinct. It's easy to navigate, because there are usually convenient gridlike paths or tracks around each square. And it's specifically planted and managed, so each square has a particular height, both of tree and often underbrush, completely distinct from adjacent squares. A few have been cleared leaving impromptu meadows.
But somehow, it feels less wood-y (I think of that as "bosky") in a way I can't clearly describe, as other woods, even small ones, that are more mixed. I don't know precisely what the difference is, if it's just the look, or if it's smell or similar.