maurits wrote:
Villa Pamphili is a great place to run. If you're at the Pantheon, you should be able to get there in maybe 3-4 miles of running. You'd cross the Tevere into Trastevere, run through the heart of that neighbourhood (quite nice), and then up steep steps and a road towards the Eastern gate of the park.
You should look up your route on the map before going. The last half mile or so will be unpleasantly traffic-heavy, including one very annoying road crossing, but once in the park you'll easily forget about all that.
Also, note that Villa Pamphili is bisected by another busy road. They've constructed one walkway over the road, roughly in the middle. So don't think you've seen all of the park if you hit a road.
This guy hit it on the head. From the Pantheon, Villa Pamphili is you best bet. You can run there directly and the park is pretty expansive with a few different little areas that can spice things up. To get there, your best bet would be to go south from your hotel to the Largo Argentina tram stop (#8 tram I think, it is the end of the line) and follow it west across the river. At some point just on the west side of the river, you will need to take a right and try to get uphill. The east enterance to the park is at the intersection of via aurelia anticaand via di san pancrazio (also the north and south borders). I would google map "rome, italy". For reference points, if you look for the island in the middle of the river, the bridge you would cross on is just west/north of there.
You have a few other options. I didn't enjoy running along the river, but it is pretty straightforward. There are a number of hobo camps under bridges though. One place I did enjoy was the circus maximus. It is kind of cheesy to do long runs there, but a full loop is about 1000m(1k) so it makes measurements easy. I used it for occasional 20k runs. You probably would want to take public transportation to get there, though, because running through the city sucks.
There are a pair of parks, villa borghese and villa alda (sp?), further in the north of the city. Again, you would probably want to use public transportation to get there. The second is suppose to be larger, but I never could find it (a bad sign maybe, or I could just be too dumb). Villa borghese is nice, but maybe not after 10 miles.
I think you should look at villa doria pamphili. It is where I did most of my running. And enjoy your trip, Rome is awesome.