I was contemplating routes between the Chester area & the Camping & Caravan Club site NW of Bala and encountered the following.
I found it on the A5 west of Corwen, between Maerdy & Dinmael (I've no idea if it occurs elsewhere). If I view the map so the little scale bar in the top right corner of the map says 1000ft there is a minor road shown leading NE from near Maerdy, just North of the A5, joining up with other minor roads passing N of Dinmael. If I zoom in one level (500ft on the scale bar) that minor road disappears from view, only to reappear when the map is zoomed in again (300ft). Cycle.travel will quite happily route along the road at the "500ft" zoom even though it isn't visible so it "knows" it is there. Is it simply a rendering problem? Or a mapping problem with that particular minor road?