we are interested in spending part (at least half-a-day i would assume). we want to see the catacombs (sebastiano, et al), walk a little on the apian way -- it just seems a bit of a hike getting there and back. are there bus routes that get you somewhat close to the catacombs, or should we resign ourselves to lots of walking? ...or should we skip it and go to the borghese gardens intead??

We took a cab from Piazza Navona to the catacombs, 10 E or so and well-worth it. There is bus service but it seems very sporadic, especially on the weekends.

There's the Archeobus, which goes to the catacombs and the Appian Way. Search here for a fairly recent thread about it.

Thank you both!

i guess one of my concerns was the return trip -- KathleenMc, i can imagine having no trouble finding taxis around P.Navonna, but what about the trip back? are there taxi stands around the park periphery?

Absmwff, if you do a search you will find LOTS of information on the catacombs and the tranportation options from the central city, including very detailed metro/bus directions from a poster named Paradise Lost.

There was a pretty regular stream of tourists arriving by cab, so we didn't have a problem. This after waiting an hour for a scheduled bus that never came(at my cheap husband's insistance!) We were there on a Sunday
afternoon in June, so I suppose it is possible the return cabs might be fewer at slower times of the year.

Try to go the the Appian Way on a Sunday when the roads are closed to through traffic. I believe yo can rent bikes as well. Walking the Appian Way on a sunny Sunday afternoon was one of the most pleasant experiences I've had in Rome. I took the bus back in the late afternoon.