transportation to Catacombs

I took the Archeobus to the catacombs and on the same ticket it also took me to the Claudia Aqueduct and the Caracalla Baths. I don't know what the current route is. fyi there are some roads in the Aqueduct Park that have high walls on both sides and zero shoulder to walk on, making for some dangerous walking

Thank you for the respose. I should clarify my post and specify that we are only interested in seeing one set of catacombs and the Quo Vadis church and that's one of the reasons we were thinking of just taking a taxi from Rome centre to the Quo Vadis Church, then taxi to San Callisto catacombs, then taxi back into centre of Rome. For this reason, we thought maybe a taxi would work better for us, but we're unsure of taxi availability at the Catacombs or Quo Vadis Church. I apologize for the confusion, but welcome any input! :)
Thank you.

To save you some money, you could look at the 218 or 118 bus, depending on where you're starting from. Often taxis are "phoned" to pick up tourists at the catacombs and the meter STARTS running when they get the call, no matter how far they must drive to reach your location. So unless you're lucky enough to catch a taxi as someone is being dropped off at the catacombs, the fare rate could be quite variable. This posting. Catacombs of San Callisto, has a few of the bus options outlined.

We took a taxi to the catacombs (15 euros) but ended up taking the bus back since you have to call for a taxi or try to grab one dropping off other people.