Myself and the good lady try to have a week up north each year exploring on our bikes. We love a bit of forest track riding. Been to Aviemore a few times for suitable stuff.
Saw a post on here mentioning Ballater and Aboyne.
Is it worth a trip ?
I'm not sure if you're after Ballater Trails ( ie enduro/ forest very close by) or area as in the stuff you'd do based there if you'd driven miles from England to get there ( ie anything north east of Glenshee ski centre)...
I'll go with the latter since loads of people know the woods much better than me ( only done ET, Mastermind and Heartbreak Ridge)
Here's my thread from a family trip a few years back. ( the Ballater info is quite late in the thread)
https://singletrackworld.com/forum/topic/family-planning-help-needed/
And a naekids trip earlier this year...
https://singletrackworld.com/forum/topic/big-rucksack-big-mountain-big-day-out/
The Pictish Trail goes through there, linking Ballater to Aboyne, along the cycle route by the R Dee. A spin back along the B976 would make a nice loop.
South of Aboyne is the Fungle Rd, which climbs to 600m, but your could turn east and come back by the Forest of Birse from about 400m high on the route.
The Deeside Trail has a mix of riding along both sides of the Dee through that area too, from Banchory.
You've been to Galloway have you?
Loads of stuff between Linn of Dee and Ballater, including Balmoral Estate. We like Braemar as a small town (village really) but there's certainly more choice of accommodation in Ballater. I think you could fill 5 days decent riding.
Derry Lodge/Glen Derry/Luibeilt.
Balmoral.
Loch Muick.
Would all be on my list.
We are near Aboyne at the moment. Loads of riding in the whole area. We have been coming here for years.
If it's forest/gravel track riding, then there's heaps all over Deeside.
Option 1 - start from Cycle Highlands in Ballater, head to the Bridge of Muick (to the SW of town), then follow small roads and tracks on the W of the river, head up as far as you want (you can end up at Loch Muick if you keep going) or loop back via Balmoral estate tracks.
Option 2 - Glen Tanar. Beautiful Scots Pine forest, with miles of tracks (closer to Aboyne)
Option 3 - Braemar/Linn of Dee and loop back around via Mar Lodge and across to the River Quoich area (amazing swimming and picnic spots). Also easy to take in various estate tracks across to Invercauld estate. I keep seeing a track being built on the S side of the A93 between Invercauld Bridge and Braemar, which looks mostly complete now (it's been getting built for the last few months), so that should make it a nicer return back to Braemar (riding on the A93 at that spot isn't great)