Where is it? Down in Mitcham, south London, about half an hour's brisk ride from the Elephant and Castle through Brixton. Mind you, any ride through Brixton is best done briskly.
What's it like? A mainish residential road running off a busy roundabout junction. Nothing to write home about, though no point writing home about anything in London: given the speed of the post, you'll arrive home first anyway.
Why bike there? You might be going to Figge's Marsh, the park at the western end, or perhaps to the allotments in Eastfields Road at the eastern end. Or you might just be lost. A few yards north, up Streatham Road, is a decent Halfords with a good selection of Real bikes (mudguards, rack, chainguard, three-speed hub gear, leather saddle) for £230.
Is it a good place to lock your bike? Not really: there's no bike parking, only street furniture. In fact, the best place is probably the sign for the road itself. No wonder the posties have to leave their bikes unlocked here while not delivering the postcard people haven't written home about Locks Lane.
It's recommended you use two locks to secure bikes in London, which is why we didn't go for the inadequately singular Lock Chase SE3, Lock Close UB2, or Lock Road TW10. Both your locks should be at least 'Sold Secure' bronze standard (ignore makers' own ratings). You can buy gold-standard locks at the Halford's near Locks Lane. There is a bike rack to lock your bike to while you do so, but unfortunately it's not fixed to anything.