Hi, if you tap on the Search botton on the map, make sure the Destinations tab is selected and search for Roma, you should be able to find it in the list. However, note that its listed with the region where its located in and appears as “Roma, Latium”. See the attached image.
Alternately, you can locate it on the map and tap on it to get the Info Panel at top, then tap the star icon on it to download. If you have zoomed all the way into it so only Rome/Roma is showing on the map, you can press the ‘i’ button at top right instead to see the info about the place in the currently onscreen.
Let me know if this helps!