It was a giant cloud that looked like a tsunami enveloping the skyline along the Romanian Black sea coast.
The gray, billowing cloud with a white edge appeared in the sky at the Black Sea resort of Mamaia on Tuesday was quickly snapped by tourists.
They uploaded the images on to social media including the “Furtuni Romania” weather group in what is one of the most photographed weather events of the summer so far.
The cloud is called a shelf cloud, a stunning feature of many spring and summertime thunderstorms.
Other than for their incredible beauty, shelf clouds are usually newsworthy because they tend to freak people out.
The cloud came before a storm on Tuesday afternoon.