Hey, there was some barriers there but I thought that was just to stop cars? I assumed bikes were allowed as I see some others go past them and plenty of walkers.
Damn, the Nat Trust website still says "The Zig Zag Road at Box Hill is now closed with no through access for cycles or cars. Please do not drive or cycle here. Box Hill car parks are closed, please do not travel here."
Seems pretty clear!
Edited to add: The Zig Zag is privately owned, not a public right of way.
There are other rights of way up the hill. Will post an update later if they're open.
Update: No sign of any closures of the Box Hill rights of way on the
Mole Valley website. So if you wanted a bracing offroad climb you could take the bridleway from the bottom of the Zig Zag (just to the right), which goes directly up to the old fort. Reckon I last did that in 1985 on an old 5 speed racer!
The Nat Trust website sets a disappointing tone of what they think of cycling (a legally permitted activity during lockdown), but as far as I can see there is nothing (in law) to stop you using that bridleway. You might encounter grumpy yokels with pitchforks...