The OP seems to be in Rome only for 2 days.. IMHO, the Roma pass is expensive..
My reasoning is ..
Normally we will be going in metro/ bus from our hotel to the 1st point of interest and then walk around.. I mean for eg. we go to colloseum , then we walk around the forum, circus maximus, vittoria emmaneul monument, travi fountain, spanish steps, pantheon etc.. these are all walkable distances though it would take the whole day for u to cover these.. but thts the fun, to walk around rome and get a feel of it..then at night u return back to hotel in public transport..
the next day u again take public transport to say vatican mueseum .. its huge and if u r lucky u can manage st peters dome also , and then a walk on the tibre river on one of the beautiful bridges..IIRC the colleseum costs max Eur 11 (depending on if some temp exhibition is there) and forum is free with it and this is valid for the next day also..vatican museum or dome is not included in the roma pass..
So , we max use the transport for say 6 times, and save entry fees to colloseo which is 11 eur, so its 17 eur.. if we hv only 2 or 3 days, I would not go to more museums, since vatican itself is amazing.. and u hv so many beautiful chuches..
I was thr for 3 days in December and did not buy the roma pass.. and can say I did not regret .. but these´r my thoughts only
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