01
Itineraries built around altitude, not distance
Above 3,000 metres you sleep no more than about 500 metres higher than the night before, and there is a genuine rest day every third or fourth day — not a shorter walk relabelled as one. On Everest Base Camp that means acclimatisation days at Namche (3,440 m) and Dingboche (4,410 m). Compressing those two nights is the most common way a fortnight in the Khumbu gets ruined, and it is usually done to save a lodge night.