When she returned, the bus had left, along with her personal belongings including her phone, wallet and passport. Her friend on the bus asked the driver to stop but she refused.
"She continued driving. She told me it was my fault and that's why she left."
Ms John said she was reduced to tears.
"I didn't know what to do. I have never been in this situation before."
Luckily a staff member at a nearby i-Site came to her aid, calling ManaBus to ask the bus driver to stop so she could hop back on.
Ms John said the company initially offered for her to take the next bus back to Auckland, which would arrive at Waitomo Caves in six hours.
However, after a lengthy discussion, the bus driver agreed to stop for 20 minutes.
The i-Site staff member used her own car to drop Ms John off at the waiting bus.
"I cried the whole time. What she did was so nice."
Ms John said when she hopped back on, the bus driver simply said, "What a girl."
"She didn't even apologise. I was really disappointed."
Ms John complained to the company, which yesterday offered to refund her $24 ticket and give her an extra free bus fare.
She was told the bus driver had been spoken to, and given an assurance it would not happen again.
ManaBus operations manager Greg Evans said the bus company had dealt with Ms John's issue on a "private level" and he would not comment further.
Last week, three Chinese students saw more of New Zealand than they bargained for when they ended up in Tauranga instead of their planned destination of the Waitomo Caves.
The trio booked return bus tickets from Auckland with ManaBus and Nakedbus for a Queen's Birthday outing to the Waitomo Caves.
But their journey instead took them from Manukau to Tauranga - 114.6km away from the hotspot - after they didn't realise they had to switch buses. NakedBus did not comment. The trio were later offered a free trip from travel firm Stray, worth $565 per person, to take them to the caves.