Toward the end of a 2 week trip to England next August, we (me, DH and 21-yr-old DD) will spend a day getting from York to near Canterbury. What is your opinion of this possible itinerary?

Leave York after early breakfast (have BandB booked, will have had most of the day in York the day before)
Drive to Lincoln, spend 3-4 hours, see Cathedral and Castle at least
Leave Lincoln no later than 2 pm
Drive to Cambridge, spend 2-3 hours, nothing planned, eat early dinner, (just sorta hang out to try to avoid some of rush hour traffic on M25), leave after 6
Drive to Dartford (have points for free room at Hilton Dartford Bridge)

Dartford would put us about an hour or so away from Canterbury (45-50 miles) if we want to go by there on our way to Dover the next day. (Also staying in the Dartford area would leave us the option of going EITHER toward Canterbury OR directly to Dover the next day.)

If we are really tired or if weather or traffic are interfering, we will probably have to skip Cambridge.
The next day, we could go straight to Dover if we’re too tired to try to see Canterbury.

I know that both Lincoln and Cambridge (and Canterbury the next day) could take days to see, but on the list of what we wanted to do this trip, these took a bit of a back seat.

So since we pilgrims are not going by way of the Tabard Inn on our way to Canterbury, (Ha), does this sound like a long drive and too little time in a couple places, but still doable? And will leaving Cambridge after 6 let us avoid most of the rush hour nearer London and still get to Dartford before dark?

It's just about doable but VERY tight. Your itinerary leaves no margin at all for being stuck in the almost inevitable roadworks, getting lost driving in/out of the town centres mentioned and trying to find parking spaces or waiting for the park & ride bus (Cambridge in particular is about the least car-friendly place in the UK).

Probably best to play it by ear and be prepared to drop Cambridge if the delays stack up.

Oh, meant to mention one more important detail. Unlike hotels, B&B's usually serve breakfast in a fairly narrow timeslot (e.g. 08:00 to 09:00). Don't count on the B&B owner looking too kindly on requests for b/fast and check-out before this time. Realistically, I doubt you'll be on the road before 09:00, which will set the pace for the rest of the day.

It sounds a lot in one day to me, but doable, and you have a plan B.

It is only about an hour from Cambridge to Dartford so leaving after 6 should be fine - it will be light until late in August so that won't be a problem.
Don't forget to have one pound fifty handy for the toll!

It is about an hour to Dover, depending on road conditions, and Canterbury is on the way so you can easily decide whether you want to visit the city or not. Parking in Canterbury is expensive and at weekends hard to find, so be aware of that. Plus driving in the city can be a right pain.

"still doable?"

No.

York to Lincoln to south of Peterborough is a nightmare of two-lane roads, getting stuck behind potato lorries (or whatever it is they're harvesting on our prairies at that time of the year) hanging round roundabouts and inevitably getting stuck behind a gaggle of caravans.

In your timescale, dump Lincoln, drive straight down the A1 and pop into Stamford if you get up really, really early. More sensible yet, since an hour in Cambridge is dunderheaded (it takes at least that long to get from a car park into town), go straight to Cambridge, then if you've got time double back to Ely.

From Cambridsge south, your only problem is unpredicted roadworks and volume of traffic. But the triangular trip via Lincoln will kill.

Whatever you do don't eat dinner at the Hilton Dartford. I did once and it was one of the worst meals I've ever had! You'll be 5 minutes drive from Bluewater, which has umpteen places to eat, and a cinema if you still have the energy!

Thanks, as always, for advice!

Have decided to leave York whenever we can, go to Lincoln (I really want to see the Cathedral and our 3rd Magna Carta!) and then head to Dartford Hilton sometime, skipping Cambridge this trip. This gives us a much slower day and builds in time for slow highways. I hope. No schedules to keep except arriving at the Hilton in time to sleep! I'm thinking we won't try to hit the M25 until after 6:30 and probably get to hotel by 8 or so. So we won't be eating in Dartford but somewhere along they way (or big late lunch in Lincoln and pack snack for dinner).

Lincoln to me is one of England's finest cities - yup with the castle area on the hill, etc. Even a quick look at it is fantastic.

Stamford i liked as well but it is in no way IMO as awesome as Lincoln