400
The translation of:
“Portitor has horrendus aquas et flumina servat//
terribili squalore - Charon, cui plurima mento//
canities inculta iacet, stant lumina flamma,” 6.298-300
The terrible ferryman of a frightening dirtiness watches over these waters and the rivers - Charon, to whom very many overgrown white hair lies on (his) chin, (his) eyes of a fire stand (fixed).