From the titanic roc of Sinbad's adventures to the giant eagles of Lord of the Rings, fantasy is rife with massive, mystical birds of prey. However, there are certainly some birds in the real world that come pretty close if you had the rare chance of a personal encounter with them.

The biggest contender is the South American harpy eagle, one of the largest (if not the largest) species of eagle on the whole planet. It can stand up to five inches in height and has claws even larger than a bear's!

Fantastic facts about the world's largest eagle

2011 Summer TCA Tour - Day 4
BEVERLY HILLS, CA - JULY 30: San Diego Zoo trainer Cari Clements and Toruk the Harpy Eagle with TCA press members speak during the 'Nature 30th anniversary season: Jungle Eagle' panel during the PBS portion of the 2011 Summer TCA Tour held at the Beverly Hilton Hotel on July 30, 2011 in Beverly Hills, California. Photo by Frederick M. Brown/Getty Images

There are also plenty of other facts about the harpy eagle that are very similar to many of its fictional counterparts. Some of these can really stir the imagination!

1. They live in the upper forest canopy.

Harpy eagles are known to live high up in the forest canopy of South America's different rainforests, including the Amazon. Remember, these forests can get as high up as over 100 feet and these magnificent birds often choose the tallest and sturdiest trees to live in.

Therefore, it is really something to picture a creature that is nearly human in height, dwelling that far above the thick canopy, ready to swoop down at a moment's notice. The imposing height of its abode is seen and possibly feared by all the rainforest's creatures.

2. They are strong enough to pick livestock.

It has been estimated that the harpy eagle's strength can lift well over a hundred pounds. That is enough to lift even something as heavy as piglets and smaller goats! However, there are far more partial to preying on monkeys and other rainforest primates.

Still, that has certainly not stopped these eagles from coming into conflict with nearby farmers. Living someplace close to a nest may very well increase the likelihood of losing some valuable livestock to these feathered forest kings.

3. Their head feathers make them almost mythical.

The distinct, intimidating shape of the eagle's head feathers left such an impression that even ancient Mayans preserved their likeness in their folding codices.

In other cases (such as when Western scientists first encountered it), its shape and massive size strongly resembled the mythical harpy that it was named after. And while it is very much a real and natural bird of prey, locals should not be faulted for having some superstitions about it.

World's largest eagle faces equally large threat

Despite its awe-inspiring size and appearance, the harpy eagle is yet another tropical eagle species threatened by deforestation. Many of its preferred habitats are often targeted by timber companies, and this is further worsened by the continued presence of illegal logging syndicates. Furthermore, the risk that the species poses to livestock is often the excuse used by trophy hunters and fearful farmers to even shoot the birds on sight.

The good news is that the eagle's increasing cultural and scientific importance has driven stronger action that would see their habitats protected against man-made threats. And while there still more to be done, healthier populations give hope that the real world will still have its fair share of fantastical birds.