Over the weekend more than 500 cars parked on mountain roads in Snowdonia, with people camping in laybys to hike up Snowdon.
Snowdonia National Park Authority said it was holding "urgent talks" to plan and agree a way forward after chaotic scenes near Snowdon.
Snowdonia and the Brecon Beacons national parks were closed at the start of lockdown, after 'unprecedented' crowds flocked to Snowdon and Pen y fan despite advice against non-essential travel.
Car parks and paths reopened in Snowdonia on 6 July to visitors for the first time after the stay local travel restrictions were lifted.
On Sunday, pictures were shared on social media of cars parked along the side of the mountain road, as people flocked to hike to the highest peak in Wales.
Nia Jefferies, who had cycled from nearby Porthmadog on Sunday, said it was "frightening" as people had parked on bends, turning it into a "single track".
"There were walkers there, motorbikes there, cyclists and big campervans, and it was down to single file," the Gwynedd councillor said.
Ms Jefferies said people were camped in laybys, and the Sherpa bus to bring hikers to the mountain could not get through due to the "reckless parking".
Hundreds of people were fined by police, but with the fine only being about £30, Ms Jefferies said it was not a deterrent.