Ordnance Survey Landranger series, the ones with the pink cover, 1:50,000 scale.
Unless you live on the edge of one, or do very long rides, you'll find one map covers a lot of ground, and the newest ones have some cycle routes marked - and they all show bridleways. Just the level of detail you need, and easy to read once you are familiar with them. And contours. If you don't know how to read contours, learn (basically, the closer the lines are together, the steeper the hill), and you'll be able to assess the hillyness of any ride easily.
In Cheshire, you'll be looking at map number 117 to start with I should think, looking at the chart on the back of the one I have handy.
Available from Smiths, and good bookshops.
It might also be worth seeing if your local council/tourist board does any cycle specific maps.