I'm looking to do some rides further afield this year, to explore some roads I haven't been on before, but still close enough that it could be done as a reasonable day trip. I bought a book called 'Lost Lanes' (https://www.amazon.co.uk/Lost-Lanes-Glorious-Southern-South-East/dp/0957157312 ) for inspiration. It's got 30-odd routes around the south-east of England, but is more geared up for people going at a leisurely pace and not necessarily on a lightweight road bike: many of the rides are under 30 miles long and feature off-road sections. Also, the rides tend to start and finish at railway stations, but I think it's probably easier and cheaper to drive (as otherwise you'd have to ride to/from Paddington or Waterloo or wherever before and after the train journeys to/from the actual ride). So I've used the some of the rides in the book as a starting point, but re-routed and elongated them and often chosen a more suitable starting point. The idea is that all of them should be less than a two-hour drive away.
These are the routes I've got:
Kent/Sussex - 55 miles to/from Shadoxhurst (near Ashford), 1 hr 20 min drive down the M20, mostly flat, heading through Romney marshes, to the coast in the shingle wilderness of Dungeness, and passing through Rye. You could get a very fast train from Stratford to Ashford, but it's pricey. https://www.strava.com/routes/12125522
West Sussex South Downs - 53 miles to/from Blackdown (near Haslemere), heaths, woods, hills, probably covering some of the route of the Velo South event (I haven't actually checked) the route fiendishly finishes with a climb to the highest point in Sussex. You could get a train to Haslemere from Waterloo / 1 hour 30 min drive down the A3 https://www.strava.com/routes/12125751
Hampshire - 40 miles to/from Easton (near Winchester), similar to the ride above but further west, 1 hr 40 mins down the M3 or train to Winchester from Waterloo. https://www.strava.com/routes/12125860
Thames Valley / The Chilterns - 48 miles to/from Stokenchurch (near High Wycombe), about 1 hr 10 mins up the M40 or train to HW from Marylebone. A ride of two very different parts: one hilly and the other flat. https://www.strava.com/routes/12130354
The Cotswolds - 64 miles to/from Combe (middle of nowhere beyond Oxford, quite near Blenheim). Nearly 2 hours' drive up the M40 / train from Paddington to Hanborough. A bit of a trek this one, but taking in loads of the famous places in the Cotswolds such as Burford, Lower Slaughter, Bourton-on-the-Water. Quite a bit of climbing. https://www.strava.com/routes/12131523
Herts / Chilterns - 47 miles to from Watton-at-Stone (near Hertford / Welwyn Garden City). This is the closest one, just 45 mins' drive up the A10 or a short train journey from Finsbury Park to Knebworth (or from Tottenham Hale to Hertford East). Gets quite hilly in places. https://www.strava.com/routes/12131733
Suffolk - 68 miles to/from Grundisburgh (beyond Ipswich). About 1 hr 40 min drive up the A12 or get the train from Liverpool Street to Ipswich. A long ride, but fairly flat, taking in the Suffolk countryside and then heading to the coast at Dunwich and Aldeburgh. https://www.strava.com/routes/12132818
I won't be doing any of these until the weather gets better, but hopefully will do approx one a month from April through to September. I'm happy to do them solo, but if there's interest in doing a B/C group pace club ride with various people driving, I'd be up for that.