Thanks for the ideas guys.
CaptainFlashheart – Yes, the Ridgeway was something that we’d thought about, but haven’t gotten around to yet. Not heard of the Wayfarers walk before – but like the look of it, and will investigate more.
nedrapier – I agree, there’s lots to explore in Surrey, and I often head off exploring to a greater or lesser extent.
For this though, we like to get away for the weekend – rather than just a day trip, with the bikes just being the focus of one day.
IHN – that looks cool… and it looks like the source of the Thames is there too. Would prefer to be off road, but will check it out in more detail.