Victoria Falls is one the biggest and most awe-inspiring waterfalls on the planet.

Spanning the width of the Zambezi River—more than a mile across—this legendary waterfall cascades over the lip of a large plateau of volcanic rock and plunges as much as 354 feet. It generate mists that can be spotted from more than a dozen miles away, which is why locals have dubbed it Mosi-oa-Tunya, or "the smoke that thunders."

But while the flow has been slicing slowly through this plateau on the national border between Zambia and Zimbabwe for some two million years, extreme swings in rainfall brought on by climate change threaten its future.

Victoria Falls is getting drier and hotter. While the region still sees roughly the same annual rainfall, those rains are compressed into a smaller period of time. Temperatures, too, are rising—in a July 2018 paper, South African researcher Kaitano Dube found that the average daily high temperature in October has warmed 6.8 F (3.8 C) from 1976 to 2017. Last year, the area suffered its worst drought in a century, bringing the falls to a trickle in December.

This extreme weather threatens not only the majesty of the falls, but also the health of its ecosystem and the local economy. The Guardian reports that recent droughts have caused power cuts in both countries, which rely on hydropower from the downstream Kariba Dam. (Learn how climate change is contributing to global economic inequities.)

Life-giving waters

The mists of Victoria Falls sustain a rainforest-like ecosystem adjacent to the falls and on the opposite cliff that faces them like a dried-up mirror image, thick with mahogany, fig, palm, and other species of vegetation.

The national border between Zambia and Zimbabwe lies midstream, and national parks of both nations exist on either side of the Zambezi. The gorges and cliffs below the falls in these parks are prime territory for raptors, including falcons and black eagles.

Humans have long relied on the falls, too. Stone artifacts from the hominin Homo habilis have been identified near the falls and show that early humans may have lived here two million years ago. More "modern" tools also evidence far more recent—50,000 years ago—Middle Stone Age settlements at Victoria Falls.

Modern tourism

Today, tourism is essential to driving economic growth. Several hundred thousand visitors from around the world trek to the falls each year. Hotels, restaurants, campgrounds, and other tourist businesses have cropped up to cater to them.

The beauty of the falls lies in their natural state, but the area is at some risk of runaway tourism-based development—more resorts, hotels, and even a possible dam below the falls that could flood several park gorges. Operators in the area offer everything from helicopter overflights to bungee jumping, and the management of these activities while preserving a quality visitor experience for all is an ongoing challenge.

Planning a trip to Victoria Falls? Here’s what you need to know.