Cyclists are signed E out of Dartford on NCN1, but the route is fiddly at the start and then runs beside the 8-lane A2; not a good experience, or up to Cycle Orbital standards. The alternative here, with the exception of a couple of short passages is a tremendous ride, and much nearer completion than NCN13 on the opposite shore. I hope Cycle Orbital can help expedite the necessary improvements, not least because the continental tourist from Dover will be spared the awful ride past Bluewater on the edge of a quasi-motorway, and approach the capital instead largely off-road with stunning riverside vistas.
So: turn L out of Dartford and take the bridge footway over the River Dart, L under railway and on the shared path on Central Rd [see below for instructions to the Dartford Crossing]. A short section on the Fast Track busway, then follow NCN125 signs round the new developments built over the River Isolation and Fever Hospitals. NCN125 ends by taking the old horse-drawn ambulance tramway 1.7 (you can see the old cobbles where the asphalt surface is worn). Now up on the riverside 2.4 is where NCN1 should (and will!) join - having crossed the Darent at the flood prevention barrier - for the stunning journey to Gravesend.
It starts well, passing under the QE2 bridge, on a newly hoggin-ed surface. At Crossways Boulevard 4.7 L into Asda carpark and onto a NCN1 fragment through pretty Greenhithe, after which into Ingress Park 5.3 riverside development, at the far end of which 5.6 the story gets interesting.
Follow the track round the last of the housing and find a cycle-permeable gate and concrete barrier to prevent motor cycle joyriding - porterage necessary 5.8. Starting as a road follow DS1 signs through the wetlands and heaths of Swanscombe on a track to Botany Marsh, where suddenly the high-grade cycleway resumes 6.9, protected from joyriding by excellent cycle-permeable gates (if not here, why not earlier?)
Back on a main road very briefly past Ebbsfleet United FC, L Grove Road 7.9, which becomes forbidding for few metres of foot and cycle path 8.3 – caution, shallow steps – on through a run-down cement depot*, until you pick up NCN1 9.7 for a final shoreline leg to central Gravesend and Pierhead.
The area around Crete Hall Road is being extensively redeveloped (2020); this was where the celebrated Rosherville Gardens flourished. One of the largest and most popular Victorian pleasure gardens, it survived for seventy years, from 1837 and finally closing to the public just before the First World War.
The Tilbury ferry is approx. half-hourly, and a fun few minutes. Spin-off 3 awaits at Tilbury Ocean Terminal). Gravesend's history is interesting; a tourist information centre will provide details, but the most famous person to die here was Pocahontas, and her statue is in the churchyard. This spinoff continues to end half a mile on at Gordon Promenade for a vista of the widening estuary towards Southend and the sea.
*If this short section sounds too intrepid, at 7.9 take B2175 through Northfleet, L Granby Rd cycleway to rejoin R Crete Hall Rd 8.8. No cycle provision on a narrow road and a dull ride, though...
[To cross the Thames by the Dartford Crossing: R Temple Hill 0.2 then Littlebrook Manor Way, R into underpass after Holiday Inn Express for signs to Dartford Crossing and the signed wait area for a free lift to Thurrock and Spinoff 3]