On the spur of the moment, Mr Ng Kang Leng, 76, decided to set off on a hike last Saturday afternoon.
He ended up getting lost in the jungle and, because he had been unprepared, had no food, water or a torch.
For the next 45 hours, the retired primary school teacher wandered around and slept in the wild until a search party found him on Monday afternoon.
To quench his thirst during his ordeal, he drank water left inside discarded capped plastic bottles, which he had found.
When he got hungry, he ate plants such as young fern fronds.
Mr Ng told The New Paper yesterday from his bed at Ng Teng Fong General Hospital in Jurong: "I didn't know what to eat so I took small bites of plants. I knew that I had to spit them out should I feel any burning. I followed my instincts.
"I'm also diabetic and did not have my medication when I got lost in the forest."
He added that he came up with an ingenious way to beat the heat. With a smile, he said: "I took off my underwear and dipped it in a river. I then wrapped the wet underwear around my neck to keep cool."
The father of two children in their 40s said he had gone for his monthly art class at the Wallace Education Centre, off Dairy Farm Road, earlier that day.
When the three-hour class ended at around noon, he decided to check out the nearby Eco-Link@Bukit Timah Expressway (BKE).
Mr Ng, who prefers to hike alone, said he had previously explored other places such as Pulau Ubin and MacRitchie Reservoir.
It was his first trip to the Eco-Link@BKE, which was built over the BKE to allow wildlife to cross between the Bukit Timah Nature Reserve and the Central Catchment area. It is not accessible to hikers.
Mr Ng, who had only a whistle and his art books in his haversack, said the hike was decided upon "on the spur of the moment and (I) didn't tell my family".
"I wanted to see how the animals travel. But I found out it was not open to the public. So I took a detour.
"I followed a trail and ended up in a thick forested area. I walked until I reached a body of water. I walked another way and (came across) more water.
"It was like I was on an island. I felt as if I was going round in circles."
When he realised he could not find his way out, he called the police at around 7pm and told an operator that he was near MacRitchie Reservoir.
He was wrong. He was actually closer to Upper Peirce Reservoir.
Deputy Superintendent (DSP) Mark Yeo, the operations officer at Bukit Timah Neighbourhood Police Centre (NPC), said about 20 officers were immediately sent to MacRitchie Reservoir to look for Mr Ng.
When they could not find him, the search was widened and more than 200 officers from the police, Gurkha Contingent, national water agency PUB and National Parks Board were deployed.
Dogs from the K9 unit also joined in the two-day search.
DSP Yeo said: "We were very concerned for Mr Ng's health especially due to his age. It was a life-and-death situation."
Mr Ng said he blew his whistle to attract attention and called for help in vain. "I tripped over roots, got entangled in vines and was pricked by thorns. But I was not scared. I had to keep calm to survive," he said.
"When night came, it was not too dark, thanks to the moon. I slept on the ground on the first night and moved nearer to the water on the second."
The search was expanded to the Upper Peirce Reservoir area on the second day.
On Monday afternoon, officers spotted Mr Ng sitting by the water, about 4km from the PUB Chestnut Avenue Waterworks near Bukit Panjang.
Assistant Superintendent (ASP) Rikesh Chand Rai from Bukit Timah NPC said: "Mr Ng looked relieved and he said, 'Wah! So many people!'
"We gave him water and he drank two bottles. We also gave him bread to eat. He was covered with scratches, but seemed fine."
Mr Ng said that an officer from the Gurkha contingent, whom he knew only as Noh, helped him walk to safety.
"When we reached a slope, Noh carried me on his back. After that, we took a boat across the water to civilisation. He gave me his walking stick as a memento."
Mr Ng's son, Mr Kevin Wong, 43, said the family was thankful to the officers for their hard work in finding his father.
"It was comforting to know that people were out there looking for him," he said.
Mr Ng said the incident has taught him to be more prepared when hiking in future.
"People always say that Singapore is small. But it suddenly felt so big when I got lost," he said.
Lost in the jungle? Stay calm and stay put
Hikers can avoid getting lost in nature reserves by sticking to the trails, said veteran nature guides.
Wildlife consultant Subaraj Rajathurai, 52, said: "Stay on the trails, don't hike on closed trails.
"Know your directions, the route that you're taking and how long it takes. Having a phone is not good enough, it is better to take a compass."
Regardless of how short a walk in a nature reserve may be, it is always safer to take precautions.
It is not a public park, said Mr Rajathurai, who has been a guide for 34 years.
He encourages hikers not to start walks in the late afternoon, when there is limited daylight left.
Nature activist Ria Tan, 54, who runs wildlife website WildSingapore, said: "No one should go out alone. Be prepared when you go out. This includes bringing enough water and food for your own needs so you don't have to eat wild plants."
On Sunday night, Ms Tan, a nature walk guide for 15 years, posted on Facebook, asking for help to find Mr Ng.
She knows Mr Ng as he had attended a walk in February organised by the Naked Hermit Crabs, a group of volunteer guides that Ms Tan is part of.
So what happens if you do manage to get hopelessly lost?
Mr Rajathurai said: "Don't panic. Call the National Parks hotline or the police.
"Most importantly, stay put. Never go off the trail as it makes the search party's job more difficult."
If there is no phone reception, he said: "Head towards the sound of traffic or follow the edge of the reservoir to the nearest PUB stations. Don't go deeper into the jungle or try to swim in the reservoir."
Puzzled at how Mr Ng could have strayed from the trail, Mr Rajathurai said: "When he started, he was close to the Bukit Timah Expressway (BKE). It's strange that he cut through the forest without crossing Chestnut Avenue or BKE."
NParks advises trekkers to stay on the designated trails and to call the 24-hour NParks helpline at 1800-471-7300 if they encounter any problems.
A retiree got lost for eight hours while hiking in a forest on the fringes of Upper Seletar Reservoir.
The 53-year-old man started his hike in the morning with just a 500ml bottle of water, his wallet, keys and mobile phone.
But about 15 minutes after following a jungle footpath, he realised he was on unfamiliar ground.
Two NParks officers and a boat driver on a boat spotted him along the shoreline of Upper Seletar Reservoir.
He suffered blood clots under his toe nails and had difficulty walking immediately after the incident.
The National Parks Board conducted two searches to find lost hikers in the Central Catchment Nature Reserve. The hikers had strayed from the marked trails.
In the first case, a couple got lost while taking a walk in the nature reserve at around 10pm. They ended up spending a night in the jungle and a search team found them the next morning.
In the second case, three hikers attempted to trek on a route that is not open to the public. They were found two hours later.
Four students got lost while trekking in MacRitchie Reservoir in the evening.
Two of them swam about 200m across the reservoir to the Singapore Island Country Club to get help.
Police rescued the other two hikers later that night.
This article was first published on September 9, 2015.
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