Some tourist areas are finding it hard to cope with an influx in visitors and maintain social distancing, an MP has said.
Hywel Williams' comments come as North Wales Police removed illegally parked cars in Snowdonia again on Saturday.
Places like Barmouth and Abersoch have seen a big increase in visitors since coronavirus restrictions were eased.
"We will have to think about what sustainable tourism looks like into the future," said the Arfon MP.
Darren Millar, member of the Senedd (MS) for Clwyd West, also said there was "concern" about the spread of the coronavirus due to the influx.
But he told BBC Radio Wales' Sunday Supplement programme that without a "bumper summer season" jobs could also be at risk.
Campsites and caravan parks have reported being "inundated with calls" with people choosing a staycation since the pandemic has affected overseas travel.
"It's about trying to get the balance right, I suppose, between safety and making sure the economy is still able to recover from what has been a huge shock in terms of the lockdown" said Mr Millar.
"Among some there is anxiety about the significant numbers that they are now seeing in those tourist destinations."
But he said there was also "huge sympathy" with business owners and workers in the tourist industry as people "still want them to be able to pay their bills".
He said people also questioned whether the authorities could be "tougher" on social distancing, although he conceded it was difficult to police due to the "huge numbers".
Plaid Cymru politicians, including Gwynedd council's leader and deputy leader, have written to First Minister Mark Drakeford to express concern about the "unprecedented numbers" of visitors.
The Welsh Government said it was working with local authorities to ensure everyone's safety.
Mr Williams said social distancing was "impossible" due to narrow pavements in places like Pwllheli.
He said local people had been "very good" at sticking to the rules to try to keep transmission of the virus down but that work was "in danger of being undone".
"We are having meetings to plan locally further measures so that tourism in this area becomes sustainable," he said.