Reading Ordnance Maps for Gentle River Valley Routes

Begin With the Blue Thread

There is a particular kind of calm that arrives before you have even laced your boots. It happens when you unfold a map, trace a blue line with a finger and realise that the route you had in mind follows water for almost its whole length. Ordnance Survey maps are wonderfully generous to river walkers: water is drawn in blue, and that blue tells you a great deal long before you set foot outside.

A single fine blue line marks a stream narrow enough to step across. A double blue line, or one that thickens as it goes, shows a river with a visible bank. Where the blue is broken by black bars, expect a weir, a sluice or a ford; where it meets a bridge symbol, you have a crossing you can rely on. Look also for the italic blue names — a brook given a name on the map is usually one worth walking beside.

Learn the Green Lines That Give You Permission

Riverside paths are only as relaxing as your legal footing on them, and the map is refreshingly clear about this. On Explorer series maps at 1:25,000, public rights of way are printed in green.

• Public footpath — a green dashed line. Walking only, with a dog under close control.
• Public bridleway — green dashes with small cross marks. Walkers, cyclists and horse riders.
• Restricted byway — green dashes with a different waymark. Walkers, cyclists, horse riders and horse-drawn vehicles.
• Byway open to all traffic — green crosses; legally open to vehicles, though often muddy, deeply rutted and wonderfully quiet.

Black dashed lines matter just as much, because they mean the opposite. They are paths that exist on the ground but carry no public right of way — often farm tracks or permissive routes. Many are genuinely welcoming and countless lovely riverside strolls use them, but you are there by the landowner's goodwill. Treat stiles, gates and waymark posts as the final word, and the map as the plan.

Recognise Access Land Without Guesswork

The pale apricot wash on an Explorer map is access land: mostly mountain, moor, heath, down and registered common land, opened up under the Countryside and Rights of Way Act. Inside that wash you may wander off the path freely, which is a joy in a river valley where the best bank is often the one nobody has drawn.

Two caveats are worth holding in mind. Access land is not the same as a right to swim, fish or camp, and some areas close at certain times — usually for ground-nesting birds or conservation. Small orange dashes, meanwhile, mark permissive paths: routes the landowner allows you to use, sometimes only seasonally. In Scotland the picture is broader and most land is open for responsible access, but gates, crops and stables still deserve respect.

Read the Land Around the Water

Contour lines turn a route from a line on paper into a sense of effort. On an Explorer map they sit at five-metre intervals, fine enough to show the gentle folds a river cuts through. Widely spaced contours mean easy walking; contours crowding together on both sides of the blue line mean a gorge, and probably a steeper, rougher path beside it.

Look too for the symbols that make a valley feel inviting: deciduous woodland in green, marshy ground shown in blue horizontal dashes (often lovely, always wet), and small black dots for picnic sites or parking. Stepping stones and footbridges are your insurance policy, particularly on spurs where a swollen stream could otherwise turn you back. Where a blue line runs beside a black line of crags or hachures, expect a bank that falls away sharply — beautiful to look at, worth treading carefully near.

Plan for Gentle Miles, Not Impressive Ones

Riverside walking flatters you: the ground is mostly level and the hours slip by unnoticed. A few habits keep a route genuinely gentle.

• Measure the true distance — use the grid squares rather than a rough guess, and remember that green dashed paths are slower going than lanes.
• Check your crossings — note where the footbridges are before you need one, and count them as anchors along the way.
• Identify an early exit — a lane, a field gate or a village within the first hour gives you permission to be tired.
• Write down the grid reference of your start and finish, in case the light goes before you do.

A Landranger at 1:50,000 is fine for a broad sense of a valley, but for riverside work the Explorer's footpath detail, access land shading and field boundaries are worth the extra sheet. Fold it so the relevant square sits on top, and keep it in a clear case — wet maps are a small sadness.

Let the Map Do the Slowing Down

Reading a valley on paper is itself part of the wellbeing. You are learning the curve of a brook, the names of fields, the place where the contour lines loosen and the trees begin. Then, on the day, the map recedes into a quiet reassurance in your pocket while the water does the rest.

A map well read turns a walk beside a river into something calmer and more deliberate — not an achievement, simply an hour or two in good company with the landscape.