SINGAPORE - Her alarm was set for midnight, and she had three computers turned on, ready to register for tickets.
Finance executive Sonu Chhina, who declined to reveal her age, was not hoping to attend a football match or concert.
She was trying to get a spot on a guided walk at Sisters' Islands organised by the National Parks Board (NParks).
In its latest marine biodiversity conservation initiative, NParks has started organising introductory guided walks at Singapore's first-ever Marine Park on Sisters' Islands.
Within an hour of online registration beginning, all spots for the first such walk for the public last Thursday were snapped up.
Said Ms Chhina: "I was so excited. I waited until the day they released the spots online."
She went with her parents, both of whom flew to Singapore from India for a holiday.
They were thrilled at the chance to view more of Singapore's natural environment.
Her father, Mr D.S. Chhina, 75, is a retired agricultural scientist. It was the first time he got to see wild marine life in Singapore.
Ms Chhina's mother, housewife Narinder Chhina, 67, said she was so excited about the walk, she woke up five hours earlier than her family thinking that it was already time to set off.
Also in the group of close to 40 people on Thursday were Shin Rei, seven, and her sister Sze Shuen, four.
The girls have already had more outdoor adventures than most children their age.
Their dad, Mr Chung Swee Yit, 38, has taken them to the Rocky Mountain National Park and the Denali National Park in the US.
In Singapore, they have trekked through reservoir parks at Macritchie and Seletar.
The girls, like others in the group, were mesmerised by the diversity of marine life at Sisters' Islands.
This included moon snails, sea anemone, giant clams and a collection of starfish nestled in the sand.
Volunteer guide Ria Tan, 53, said a guide would be able to spot small creatures and plants an untrained eye would likely miss.
Besides the starfish, she was able to identify a tiny jelly-like mass of cuttlefish eggs which no one noticed beneath a large patch of seagrass.
Not too hard to spot was the giant clam, a huge crusty creature with green and yellow patterns curling across its mouth.
"It's best not to touch anything that you're not familiar with, especially with marine life - the most dangerous things can look innocent," explained Ms Tan.
Deputy director of the Coastal and Marine National Biodiversity Centre, Ms Karenne Tun, 44, said seeing and experiencing marine life was the best way Singaporeans could understand the importance of conserving it.
"We have a rich natural heritage in Singapore and it's important that we don't lose this diversity so that future generations can access it too," she said.