Ben Nevis

The trig point on the summit is the anchor for the standard escape route in poor visibility. From it, walk 150 metres on a bearing of 231 degrees, turn onto a bearing of 282 degrees, and keep going until you pick up the footpath. The walker suggests writing the three numbers down before setting off.

from the trig point you walk on a bearing of 231 for 150 metres you then turn onto a bearing of 282

The bearings given for leaving the summit are grid bearings. At the time of the video there was virtually no magnetic declination in the UK, so the numbers could be walked straight off the compass, but in later years a compass user would need to adjust for the changing declination.

they are grid bearings ... you may need to adjust for declination

If a walker reaches the summit in thick weather without a compass, the advice is to sit down, stay where you are, put on all your clothes and wait for the weather to lift. No expensive compass is needed either — any compass will do as long as you know how to use it.

sit down stay where you are put all your clothes on and just wait until the weather picks up

To follow the bearing, hold the compass flat in front of you, rotate the dial until the bearing number sits at the top of the dial, then turn your whole body until the needle sits over the direction arrow. Pick a feature ahead on that line, walk to it, and repeat, aiming off in stages especially when visibility is shorter than the full distance.

rotate the dial until 231 is at the top of the dial

To judge when the 150 metres is done, count double paces, for example every time the left foot hits the ground. The walker normally does 64 paces per 100 metres, and suggests that anyone who does not know their own pace count simply use 100 paces for the 150 metres — not exact, but near enough.

for every 100 metres I normally do 64 paces

The full sequence is: from the trig point walk on bearing 231 while counting about 100 paces, stop, set the dial to 282, turn your body until the needle is over the arrow, then keep walking on that line, re-aiming on features as you go, until the footpath is picked up.

you're going to walk for 100 paces and then you're going to stop

The summit that holds the trig point is the highest peak in the British Isles, standing at about 1,345 metres, roughly 4,414 feet.

the highest peak in the british isles standing at 1,345 meters

A walker reached the top into a near-whiteout. He and his dogs stayed only ten to fifteen minutes, hoping the cloud would lift, but it did not clear and, with the dogs getting cold, he headed back down. The famous summit building and trig were still found despite the conditions.

it's still a white out at the minute but we'll stay here for a bit and see if it clears

On the summit, past the famous old building, the walker insists the trig point has to be touched — treating it as law. It sits right at the highest point and is part of the summit ritual.

i've got to go touch the trigger. It's like the law.

The clear remains beside the trig point are from an observatory used between 1883 and 1904 to record mountain weather. Working there was dangerous — in high winds the weathermen would sometimes tie themselves to the building so they would not be blown over the cliff edge. The data it collected is still the most comprehensive record of mountain weather in Great Britain.

they would sometimes even have to tie themselves to the observatory so the high winds wouldn't blow them over the cliff edge

Like Snowdon, the top of Ben Nevis is busy enough that walkers queue to get a photo at the trig point. The pair came up the quieter Carn Mor Dearg Arete and saw very few people all day, but reached a crowded summit where they still had to wait their turn at the trig.

you still had to queue to get to the trigger point

As the cloud lifted a little, the pair said the summit left them almost level with the tops of the clouds, which made being up there feel like floating above the cloud.

you almost felt like you were sort of floating on the clouds