Menrva is the largest crater on Titan, with a diameter of 392 kilometers. This is evident by Menrva's distinct lack of a central peak, indicating modification of the crater's surface since formation. A network of channels known as Elivagar Flumina flow away from the crest of the crater into a catchment basin. (wikipedia entry)
A crater is a circular depression likely created by an impact event. On Titan they are named after gods and goddesses of wisdom.
Image Source. Marker locations are approximate and may not always appear to align with image on map.