Dead flat for the first stretch out of Fort William, following the Caledonian Canal towpath past Neptune's Staircase, Britain's longest flight of locks, to Gairlochy, where the canal gives way to Loch Lochy and the path moves onto forest track along the shore past Achnacarry. Easy, well-populated walking throughout, with Fort William's suburbs, Corpach and Banavie all close together at the start. Genuinely gentle by Great Glen Way standards, the climbing starts properly in the next section.
Navigation: Flat, obvious towpath walking with no navigation difficulty; the switch from canal to forest track at Gairlochy is well signed.
In poor weather: Fully sheltered on the canal towpath; the Loch Lochy forest shore beyond Gairlochy gives some cover too, though the open loch itself can funnel wind.
Escape options: Corpach and Banavie, both very close to the start, plus Gairlochy at the end, all have road and bus access, an easy section to adjust plans on.
Continues along Loch Lochy's forest shore before the trail crosses to Loch Oich at Laggan, where the canal reappears briefly alongside the loch. Short but with more up-and-down per kilometre than the section before it, forest track rather than towpath for most of the distance, with the trail's most repetitive short climbing so far. Quiet and remote by comparison with the canal miles either side, with only a couple of small settlements passed.
Navigation: Way-marked forest track with several short, repetitive ups and downs; easy to follow but more attention needed underfoot than on the flat canal sections.
In poor weather: Forest cover gives some shelter from wind and rain, though the loch shore itself is more exposed at gaps in the trees.
Escape options: Laggan and the locks there give limited road access; otherwise this is a quiet stretch with few options until Invergarry-area services are reached.
Loch Oich's canal and cycle-path give an easy start, then proper Caledonian Canal towpath leads into Fort Augustus, the trail's liveliest stop, a small town built around a flight of five locks where the canal drops into Loch Ness, with the Caledonian Canal Heritage Centre and a genuine holiday-town feel. Beyond it the character changes again: the path picks up Loch Ness's north-west shore, undulating through forest rather than following flat towpath, all the way to Invermoriston. A good mix of easy canal miles and quieter loch-shore walking.
Navigation: Easy on the canal towpath into Fort Augustus; the Loch Ness shore path beyond it is well waymarked but has more junctions, since low-level and high-level options can both be signed nearby.
In poor weather: Sheltered on the canal; the Loch Ness shore stretch beyond Fort Augustus is more open to wind coming off the water.
Escape options: Fort Augustus has full transport links; Invermoriston at the end also has bus access, few options in between beyond the loch-shore path itself.
The steepest, hardest climbing on the whole Great Glen Way: a sustained pull up out of Invermoriston onto the high-level route through the wooded hills above Loch Ness, reaching around 422m, the trail's highest point. Views open out across the loch and the hills on the far shore as the trees thin, a real reward for the effort. Short in distance but by far the biggest ascent per kilometre anywhere on the trail; there's also a lower, gentler alternative through forestry nearer the shore for anyone who'd rather skip the climb.
Navigation: Both high and low routes are waymarked from Invermoriston; make sure you're on the one you intend, since they diverge early and don't reconverge until well into the next section.
In poor weather: Fully exposed above the treeline at the top. Wind and low cloud can remove the views that are the whole point of taking this route.
Escape options: None once committed to the high route, it's a sustained climb with no realistic bail-out until the descent toward Drumnadrochit in the next section.
Continues along the high-level forest track before a long descent down to Drumnadrochit, the high and low routes rejoining on the way down. Drumnadrochit itself is the busiest, best-served place on the trail after Fort William and Inverness, full shops, Loch Ness Centre, the works, a proper change of pace after two remote, strenuous sections. More down than up here, the payoff for the climbing just done. A natural place to take a rest day or stock up properly before the final push to Inverness.
Navigation: Well waymarked forest track down to Drumnadrochit; the descent is steady rather than technical.
In poor weather: Sheltered once back into the forest; only the highest ground at the start of this section shares the exposure of the climb before it.
Escape options: Drumnadrochit at the end has full transport links; nothing comparable until then on this stretch.
One more climb before the finish: a steep pull up from Drumnadrochit to Abriachan, then a long traverse through Abriachan's ancient forest high above Loch Ness, genuinely wild-feeling for a section this close to a city. The trail then drops back down to the Caledonian Canal at Dochgarroch, and it's flat towpath the rest of the way, a proper anticlimax in terrain terms, but an easy, fast finish along the River Ness into Inverness. Busy and urban for the last few kilometres, ending at Inverness Castle.
Navigation: Well waymarked throughout; the Abriachan forest track has several similar junctions, but the canal towpath at the end is impossible to lose.
In poor weather: Exposed on the high forest section above Drumnadrochit; fully sheltered and unaffected by weather on the canal towpath into Inverness.
Escape options: Limited on the high forest stretch; Dochgarroch and the canal towpath from there give constant, easy road and bus access into Inverness.