The Acropolis, one of Greece's most famous landmarks, will close to tourists during the hottest part of the day Wednesday, as a heat wave scorches the country's capital. The popular tourist site, which attracts visitors from around the world, will shut its doors between 12 p.m. and 5 p.m. local time, a spokesperson for the Ephorate of Antiquities of the City of Athens told CNN, with temperatures Wednesday expected to exceed 40 degrees Celsius (104 degrees Fahrenheit). Built on a steep, rocky hill, the UNESCO-listed site is particularly exposed to heat, offering lines of tourists waiting to enter and exit the attraction little protection from the beating sun. The closure of the Acropolis has become an annual trend, as Greece — along with many other European countries — continues to experience blistering summers. In July, the site was also closed between 12 p.m. and 5 p.m. in an effort to protect workers and visitors, as temperatures soared well above 100 degrees Fahrenheit. Shelters were set up, and police and emergency services were called to provide help to tourists in difficulty due to the heat. The current heat wave in the region looks set to continue through Thursday, according to the Hellenic National Meteorological Service, which has released an orange warning for heat — the second-most serious designation. The high temperatures are sparking fears of yet another very hot summer ahead for parts of Europe, increasing the risks of a devastating wildfire season and threatening people's health. Heat is one of the deadliest natural hazards, more than 61,000 people died during Europe's record-breaking summer heatwave in 2022. A combination of human-caused climate change and the arrival of the natural climate phenomenon, El Niño, which has a global heating effect, helped push temperatures last summer up to record levels in parts of Europe, the planet's fastest warming continent. But even as El Niño fades, scientists are clear that the long-term trend of global warming means heat waves are set to become more frequent and more severe. — CNN