Darenth Parish (through which the river flows) derives from a Celtic phrase 'stream where oak-trees grow' (Irish: "dair" = 'oak-tree', "abha" = river ) (compare e.g."Derwent"). The landscapes of the valley were painted in a visionary manner by the renowned Victorian artist Samuel Palmer during the mid 1800s.
Fed by springs from the greensand hills south of Westerham in Kent and below Limpsfield Chart in Surrey it flows 21 miles (34 km) east then north by Otford and Shoreham, past the castle and the ruined Roman villa at Lullingstone, then by Eynsford, Farningham, Horton Kirby, South Darenth, Sutton-at-Hone, Darenth, and eventually to Dartford whence it proceeds a final two miles as a tidal estuary until it drops into the Thames "Long Reach".
North of Dartford the Darent is tidal and, just before entering the Thames, receives the waters of the River Cray at Dartford & Crayford Marshes where the rivers form administrative boundaries between Greater London and Kent, (specifically, the London Borough of Bexley and the Kentish borough of Dartford). The Darent enters Thames Long Reach to the East of Crayford Ness.
Kent County Council signposted a 19-mile (31 km) walking route along the Darent between the Greensand Hills above Sevenoaks and the Thames. and named it The Darent Valley Path. The route receives no obvious attention from councils or 'focus' groups although all or part is used by joggers, cyclists, walkers, dog walkers and curious adventurers, availing of The Darent Valley Path to access or view the river's amenities, such as they are. In 2016 this lack of attention is being addressed in the tidal section by a group of concerned locals "Friends of Dartford and Crayford Creeks". As of mid-2016 a trust is being formed to further the regeneration and give formal recognition to the protection of this valuable public amenity.
Currently the tidal section is being furbished and improved by volunteers of "Friends of Dartford and Crayford Creek". to permit marine traffic, such as narrowboats and leisure cruisers to sail up to Steam Crane Wharf and beyond, to overnight or stay awhile. Much mud was laid down by river and tide from 1986 when the Creek was effectively abandoned. The tops of some mudbanks are now some two metres high; while others would need only minimal adjustment to accommodate the movement and docking of largish craft with no impact on the nature of the river. Work parties surveyed, cleared and removed hazardous debris from the river bed to permit safe passage of all types of craft during low water. Volunteers and lengthsmen removed a number of self-seeded trees, lopped others and removed debris from the banks. The trust (termed Dartford and Crayford Restoration Trust) is an offshoot of the Northfleet Harbour Restoration Trust.