Lumba Sumba Pass Trek

Also known as Kanchenjunga to Makalu Traverse / Lumba Sumba La Trek (GHT link section).

Lumba Sumba Pass Trek is an advanced 18-21-day camping trek in the Kanchenjunga / Makalu region of Nepal, reaching 5,177 m. It starts at Lelep (Tamor valley, Taplejung — road head via Taplejung/Sekathum) and ends at Num/Tumlingtar (Arun valley, Sankhuwasabha).

Key facts

Region

Kanchenjunga / Makalu (Taplejung, Sankhuwasabha)

Duration

18-21 days, 5-8 hours walking per day

Distance

200 km

Maximum altitude

5,177 m

Difficulty

Advanced — A remote 18-21 day expedition-style traverse linking the Kanchenjunga and Makalu regions over the 5,177 m Lumba Sumba La, with high camps at 4,700 m, no rescue infrastructure, restricted areas at both ends and multi-day stretches without settlements. Route-finding, camping logistics and a snow-prone pass make it a genuine grade 5 despite being non-technical in good conditions.

Trek type

Camping, point-to-point route

Best season

Autumn (Oct-Nov) and Spring (Mar-May); the pass is usually snowbound Dec-Feb

Guide

Mandatory. Restricted areas at both ends: RAPs are issued only through a registered Nepali agency with a licensed guide. The former 2-trekker minimum for restricted-area permits was abolished in March 2026 — solo trekkers can now obtain RAPs, but guide + agency remain mandatory.

Restricted area

Yes — special permit required

Budget cost

NPR 300,000–360,000

Comfortable cost

NPR 360,000–430,000

Guided cost

NPR 350,000–465,000

Getting there

Kathmandu → Bhadrapur (flight 45 min) → Ilam (drive 4h) → Taplejung → Sekathum/Lelep road head (drive 7-9h, rough) → trek over Lumba Sumba La → Hatiya → Num (road head) → Tumlingtar (jeep 6-8h) → Kathmandu (flight 50 min). Direct night bus/jeep Kathmandu→Taplejung (~20h) is the overland alternative.

Altitude sickness

High — camps rise from 3,208 m (Olangchung Gola) to 4,700 m (pass camp) in three stages before the 5,177 m crossing; the built-in acclimatization day at Olangchung Gola is essential and descent options from the pass basin are long in both directions.

Weather

Far-eastern Nepal catches the monsoon earliest and hardest — June-September is essentially impossible (landslides, swollen rivers, leeches). The pass carries snow into April and again from late November; whiteouts develop quickly on the open upper basins. Lower Arun valley days (below 1,500 m) are hot and humid even in season.

Permits

• Kanchenjunga Restricted Area Permit (Taplejung RAP) — NPR 3,040 for foreigners. Where to get it: Immigration Kathmandu through a registered trekking agency only
• Sankhuwasabha Restricted Area Permit (Kimathanka/Chepuwa/Hatiya/Pawakhola RAP) — NPR 3,040 for foreigners. Where to get it: Immigration Kathmandu through a registered trekking agency only
• Kanchenjunga Conservation Area Permit (KCAP) — NPR 2,000 for foreigners. Where to get it: NTB Kathmandu or KCAP counter Taplejung (Lelep checkpost)
• Makalu Barun National Park Entry Permit — NPR 3,000 for foreigners. Where to get it: NTB Kathmandu or park counter (Seduwa/Khandbari); arrange in Kathmandu — no counter on the Thudam side

Itinerary

1. Day 1: Kathmandu to Ilam, 0 h, 1,300 m — Flight over the eastern Himalaya; Kanyam tea gardens
2. Day 2: Ilam to Lelep, 0-1 h, 1,687 m — Rough drive up the Tamor valley; KCAP checkpost at Lelep
3. Day 3: Lelep to Ela Danda, 5-6 h, 2,051 m — Gorge trail above the Tamor; entering the restricted upper valley
4. Day 4: Ela Danda to Jongim Kharka, 7-8 h, 2,635 m — Steep forested climbs and bridge crossings in the Tamor gorge
5. Day 5: Jongim Kharka to Olangchung Gola, 3-4 h, 3,208 m — Olangchung Gola — ancient Tibetan trading village with the 465-year-old Diki Chholing Gompa
6. Day 6: Olangchung Gola to Olangchung Gola (acclimatization), 3-4 h, 3,208 m — Acclimatization walk up the Dingsamba/Tiptala valley; monastery visit
7. Day 7: Olangchung Gola to Langmale (Sanjung) Kharka, 6-7 h, 3,910 m — Turn up the Dingsamba Khola toward the pass; yak pastures and moraine country
8. Day 8: Langmale Kharka to Pass Camp, 4-5 h, 4,700 m — High camp below Lumba Sumba La; alpenglow on Kanchenjunga's outliers
9. Day 9: Pass Camp to Chaunri Kharka (via Lumba Sumba La), 8-9 h, 4,595 m — Lumba Sumba La (5,177 m) — prayer-flagged crest between the Kanchenjunga and Makalu watersheds; views of Kanchenjunga, Jannu, Makalu and Chamlang on a clear crossing
10. Day 10: Chaunri Kharka to Thudam, 6-7 h, 3,556 m — Descent into the upper Arun watershed to Thudam, a single-street Bhotia yak-herding village
11. Day 11: Thudam to Thudam (contingency/rest), 0-2 h, 3,556 m — Built-in contingency day (used for pass weather delays or rest); village life among yak caravans
12. Day 12: Thudam to Yak Kharka (Kharka camp), 6-7 h, 2,877 m — Wild descent through bamboo and rhododendron jungle — red panda country
13. Day 13: Yak Kharka to Chyamtang, 5-6 h, 2,229 m — First Arun valley village; Bhote culture, millet terraces
14. Day 14: Chyamtang to Hatiya, 5-6 h, 1,595 m — Trail high above the Arun river; Hatiya bazaar on the old Tibet trade route
15. Day 15: Hatiya to Hedangna, 6-7 h, 1,180 m — Hot, terraced lower Arun; Rai villages and cardamom groves
16. Day 16: Hedangna to Num, 4-5 h, 1,560 m — Cross the Arun on the big suspension bridge and climb to the Num road head (shared with the Makalu BC trail)
17. Day 17: Num to Tumlingtar, 0 h, 450 m — Descent drive along the Arun; Khandbari bazaar
18. Day 18: Tumlingtar to Kathmandu, 0 h, 1,340 m — Flight back over the Sun Koshi hills