| Cremera | |
| Source1 Location: | Monte Silio |
| Mouth: | Tiber |
| Mouth Location: | Labaro |
| Mouth Coordinates: | 41.9872°N 12.4978°W |
| Subdivision Type1: | Country |
| Subdivision Name1: | Italy |
| Length: | 36.7km (22.8miles) |
| Discharge1 Avg: | about 5m3/s |
| Basin Size: | 103km2 |
The Cremera is a 36.7km (22.8miles) Italian stream in Lazio (and previously in Etruria) which runs past Sacrofano, Formello, and Campagnano di Roma before falling into the Tiber about 10km (10miles) north of Rome. It connects to the Tiber just as the Via Flaminia intersects the Grande Raccordo Anulare highway, on the proximity of the Labaro Roma Nord railway station, where there is an ancient Roman bridge.The identification with the Fosso della Valchetta is fixed as correct by the account in Livy ii. 49, which shows that the Saxa Rubra were not far off, and this we know to be the Roman name of the post station of Prima Porta, about 12km (07miles) from Rome on the Via Flaminia. It is famous for the defeat of the three hundred Fabii, who had established a fortified post on its banks.