The treks in the northwestern tip of Indonesia are an attempt to lift Aceh out of poverty by developing local tourism projects and reviving the crippled economy after a 30-year conflict and a devastating tsunami in 2004.
So just as tourists in Vietnam can scramble through the Cu Chi tunnels used by the Vietcong in the Vietnam war, visitors to Aceh can see where the separatist Free Aceh Movement (GAM) hid from or fought against the Indonesian army (TNI) until as recently as 2005 when the two sides signed a peace agreement.
Marjuni takes tourists on a scramble over sharp rocky trails, past teak trees cloaked in creepers, and alongside pristine waterfalls and sparkling rock pools.
This part of Aceh is home to the endangered Sumatran tiger, deer, and hornbills, as well as rather less appealing leeches.
"The area is very beautiful. I like trekking and I was interested to see what life was like during the conflict," said Hugo Lamers, a Dutch aid worker who went on one of the guerrilla tours last year.
"It's difficult to imagine but three or more years ago they were running around here with guns and fighting the TNI. When I went, they took us to a place where they had lost some of their friends. And then you realise that we are there for fun, but for them this was really serious."