As a rebel fighter, Marjuni Ibrahim hid out in Aceh's jungle. These days he leads "guerrilla tours" taking visitors with a taste for extreme hiking and an interest in Aceh's turbulent past over the same terrain.
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 realize that we are there for fun, but for them this was really serious."
Some of the hikes cover terrain where fighting took place or where visitors can see reminders of the conflict such as leftover army foodpacks and army graffiti. But a few of GAM's former hiding places still remain secret, perhaps for fear that they might one day be needed again.
Marjuni, now 28, joined GAM when he was 20, driven by "injustices, such as the murders of civilians by the TNI just because they were suspected GAM."
An estimated 15,000 people died during nearly three decades of fighting for Aceh's independence. Many others were tortured by the Indonesian military, or traumatized by the conflict.
This part of Sumatra island, once a separate kingdom, was an important center for trade thanks in part to its strategic position at the northern end of the Malacca Strait, the sea lanes linking Asia to the Middle East and Europe.
But post-colonial Indonesia had no interest in allowing a separate Aceh. The region's abundant natural resources, including oil, gas, and timber, provided revenues for the government. The army moved in to crush opposition among the 4 million Acehnese, with as many as 50,000 troops operating in the area by 2003.
Marjuni said his group of about 20 GAM fighters used to hide in the jungle for several days at a time because they knew that if they returned home, they were likely to be picked up by the army and either tortured or, like Marjuni's brother, jailed.
But every week or so, his unit had to come out of the jungle to pick up rice and other provisions at an agreed location.
"I was most scared coming down from the jungle in case the TNI was there," he said.
They drank water from the waterfalls, and if they missed their food drop, they were forced to live off a fern-like plant or whatever else they could find to eat in the jungle.
It was from high up on the jungle-clad hill that Marjuni and his unit saw the tsunami hit Aceh on December 26, 2004. The noise was so loud they thought it was an aerial bombing.
First the hill shuddered, dislodging rocks. Then in the distance they saw the sea turn black and rush inland.
"We saw it come in and we were very scared" said Marjuni, whose sister and parents were among the 170,000 who died or disappeared in the tsunami in Aceh.
While much of Aceh's coastline was destroyed, the disaster provided an impetus for both sides to pursue peace. Indonesia withdrew troops and police, while GAM fighters came out of the jungle and gave up their weapons in exchange for an amnesty.
Marjuni found work rebuilding homes and infrastructure for a couple of dollars a day. Then one day, he was approached by Mendel Pols, a Dutch citizen who had founded a small adventure tours firm called Aceh Explorer and who was looking for former GAM fighters to take groups of tourists trekking in the jungle.
"When I told GAM my idea they looked at me like I was from Mars," said Pols, who is married to an Acehnese and lives in the capital Banda Aceh.
So far, most of his customers have been foreign aid workers who are based in Aceh for the post-tsunami reconstruction. As business takes off, he plans to invest in better hiking boots for the guides, and provide first aid training.
"I want to make the Acehnese aware of the potential for community-based tourism, and put Aceh on the map as a friendly tourism destination," he said.