Rome - Temple of Fortuna Virilis
The the Temple of Fortuna Virilis was dedicated to the god Portumnous, protector of harbors and sea trade. It's from the second century, but was turned into a church in 872, which preserved it.

Behind, you can see the column of Santa Maria in Cosmedin, where you'll find the bocca della verita, an old roman sewer cover now built into the wall, in which tourists and other rogues place their arms. If they are liars, legend tells us, their arms will be severed violently. If this were true, no doubt Roman drivers would have to contend with torrents of blood flooding the streets, a fact which would not necessarily slow them down.