Quote from palinuro:
Abruzzo to the east, the Simbruini to the south. Leave Rome around 7:30, park the car by 9, and by 1 you're having lunch at 2000 meters. Of course there are easier hikes, but I usually aim for about 1000 meters of climbing.
Unfortunately winter has finally hit, and I won't be going out again until late January, and then it'll be scaled back.
For me that's one of the great things about living in Rome. You can spend one day at the beach and the next in the moutains--and still have the city as your base.