'Other than Corstorphine Hill, which doesn't really count'
!!
Corstorphine hill is aces! i've biked there since i was about 10, and regularly nip up for an hour two. i still manage to find ace new lines all over the hill, which although short, are brilliant as far as rooty technical rocky tight singletrack goes. lots of drops and chutes and climbs and steps and drops and rock and roots yadayadayada……..
anyway, maybe not ideal for a long distance ride, but for hoonin around of an afternoon it's tip top.
a wee short travel hardtail keeps it interesting too, as someone else mentioned.
*edit – as said, it can also be tied into a nice wee route out through cammo, up the river almond (where there is more really nice mint sauce type singletrack) and beyond.