ATHENS, April 13 --  Worsening wildfires, soaring heatwaves and rising water levels have prompted Greek officials to take a closer look at protecting priceless archaeological sites that draw hundreds of thousands of visitors each year.

The monuments, scattered across the country, earn Greece millions of dollars in tourism revenue.

But many of the sites are in rural areas and officials believe better planning is needed in case large crowds of tourists need to be evacuated in an emergency.

After a three-year study by some of the country's leading scientific institutions, the Greek culture ministry has earmarked 19 monuments that most urgently need protection against natural threats, with several more to be bolstered by 2030.

The mi...