The Coast-to-Coast Walk runs 192 miles through northern England from St. Bees on the Irish Sea to Robin Hood's Bay on the North Sea. Both are easily accessible by public transportation. Trains run to St. Bees and to Whitby (a few miles from Robin Hood's Bay; buses and taxis run between them).
Unlike England's other famous long-distance walks, the Coast-to-Coast is not an official trail. Therefore it is not always marked (in fact, in the Lakes, it is never marked). For the most part, it follows public foot paths and rights of way. There is some road walking, especially in villages and towns. Map and compass skills are essential. I wish I'd brought a Global Positioning System (GPS), because when mist shrouds the moors and footpaths go every which way, it can be hard to find your bearings. You can also get confused climbing over the hundredth stone wall of the day or turning onto the correct public footpath, since there are often several among which to choose.
The Ordnance Survey has put together two strip maps of the trail at a scale of 1:25,000 (Sheet 33 covers St. Bees to Keld; Sheet 34 covers Keld to Robin Hood's Bay). However, if those are the only maps you have, you'll find that they cover too narrow a corridor to provide information about alternate routes (and if you get lost, you might wander off the maps in short order). The 1:50,000 maps are listed in the available guidebooks, of which there are several.
Details mentioned in this article were accurate at the time of publication