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The Eiger Trail takes you below the north face, between Eigergletscher and Alpiglen.
Start at Eigergletscher for the mostly downhill direction: about six kilometres, two hours of walking and nearly 780 metres of descent. That is plenty of downhill walking, even though the operator grades the route medium. In the other direction, expect a sustained climb.
Check that the trail is open, and plan transport to the start and from the finish. Wear hiking shoes and carry water, food and warm layers; wet or steep sections need care. Follow signs for the Eiger Trail. The gentler Jungfrau Eiger Walk and the Rotstock via ferrata are separate routes; the latter needs climbing equipment and skills.