The 100-space car park at the start of the track 6km from Wanaka township on Mt Aspiring Rd was full before 9am yesterday.
French tourists Melanie Blairvacq and Florian Maimi said they had arrived at the car park at 3am in the hope of ''being alone'' on the hike but they found 40 others on the summit at sunrise.
''On the way back down we saw so many coming up the track and a lot of them didn't have proper hiking shoes, one person was wearing flip flops and we saw a mother with a baby in a backpack who had no water bottle or anything,'' Ms Blairvacq said.
''People just want to go up to get the instagram picture and then that is it,'' she said.
The five to seven-hour, 16km return trip was one of the Department of Conservation's most popular day walks.
The view from the summit has the reputation of being ''the most instagrammed spot in New Zealand''.
For the year October 2018 to the end of September 2019, Doc recorded 81,350 walkers on the Roys Peak Track.
The car park and walk are managed by Doc but Queenstown Lakes District Council spokesman Jack Barlow said the council's freedom camping ambassadors visited the car park every few days to educate visitors about ''the dos and don'ts'' for the car park, and hand out a new Responsible Camping leaflet.
Earlier this week, Wanaka police reported issuing 37 fines in one day to vehicles parked outside the Roys Peak car park.
Yesterday morning, the Otago Daily Times spoke to several drivers and occupants of cars parked on Mt Aspiring Rd and none of them knew they were parked illegally.
