Abyssal Reach

The Abyssal Reach is a continent-spanning cave and cavern system that encompasses mainland Sinderlan. In the ancient past, it was known to be home to some of the most dangerous creatures on Perradin. After the mythical Hunt of Chipped Fangs in the 16th century in the chaos following the Starfall, it has been devoid of virtually all life. Its main caves are permeated by a seemingly magical darkness that proves difficult and sometimes impossible to dispel, limiting access. Most entrances to the Abyss have been sealed over the centuries, but occassional breaches still occur. Rarely, small isolated chambers are discovered with some diminutive monsters still residing in micro ecosystems, however it is understood that these are mere vestiges of the types of creatures that previously dominated the Abyss.
All modern expeditions have found little of use in the caverns, which has led to them being ignored or avoided by local and regional governments of the Kingdom and Didacian Consulate. While risks associated with exploring the Abyss are similar to that of any other cave system, there have been reports of severe headaches and nausea emerging in explorers spending more than 24 hours in the Abyss. This has made the cave system an undesirable place for research and exploration for many centuries. Regional legends warn of venturing into the caves, speaking of the dark spirits of the slain monsters and ancient Blood Hunter Inquisitors still haunting their depths. 
Structural ruins have been reportedly seen in the caves' deepest reaches, but the validity of these claims are questionable.

Geography

The Abyssal Reach snakes its way through the entire continent of Sinderlan. Most of its original entrances laid in the mountains of the western and central Kingdom, while others formed alongside the banks of Sinderlan's many large rivers as they passed over rugged terrain. The nation with the highest concentration of entrances to the Abyss is the Didacian Consulate, home to nearly 200 cave openings, many formed during the buckling of Perradin's crust after the Starfall. Entrance tunnels reportedly descend beneath the surface laterally for several miles and are estimated to be roughly 6000 ft beneath the surface on average after inclines plateau. 
Ancient accounts of the main chambers suggest that the entrance tunnels gave way to enormous caverns, some with ceilings hundreds of feet high, with hundreds more tunnels snaking off into the depths. Reports of subterranean rivers and lakes flowing through some of these large chambers suggests an even larger network of submerged tunnels and chambers.
While these ancient accounts are still remembered in the present, many scholars believe them to be exaggerated. As the region is bathed in a darkness of magical nature, it makes exploration difficult. Expeditions have reported that very few useful resources are to be found in the Abyss, leading to a lack of interest in exploring further.
The ancient chambers of southern Sinderlan were fully destroyed when Velnor collided with Perradin in the Starfall. Despite this, the modern Didacian Consulate has more untouched chambers than all of the rest of Sinderlan in its northern territory. Cave-ins and collapses sealed off many small caverns before the start of the Hunt of Chipped Fangs. However, many of these caverns exist without proper entrances and are often uncovered in mining projects or in Cratersildes.

Fauna & Flora

Ancient accounts state that the Abyss was once home to terrifying beasts and monsters that are now rare or extinct. These include Beholders, Driders, Displacer Beasts, and even the mighty Tarrasque. These creatures would occasionally surface and wreak havoc on the people of Sinderlan. Ancient myths even state that Vampires were counted among the monsters of the Abyss. It is speculated that some Dragons of Sinderlan once occupied some of the upper chambers, but such claims have little evidence eons after their extinction. After the Hunt of the Chipped Fangs, many of these creatures were hunted to extinction or pushed out of the caves and into the wilds of Sinderlan's surface in the chaos of the 16th century. 
The modern Abyss is home to very few fauna after the Hunt of Chipped Fangs. The upper chambers often will have diminutive creatures, such as bats, rodents, and small reptiles as common caves often contain. The deeper chambers, previously inhabited by monstrous creatures, are mostly devoid of animal life save for insects, cephalopods, cave fish, and mollusks. Isolated chambers still containing monstrous life contain dangerous creatures such as Grey Renders, Kruthiks, and Frost Salamanders

History

The Abyssal Reach has existed since long before the settling of Sinderlan. The fortresses that became Kingdom Dwarven cities such as Hearth of Iron and Alterporton are constructed in caves that may once have been part of the Abyssal Reach, but were sealed off from the rest of the cave system by the fortresses' original builders long before the Kingdom occupied them. The main chambers, according to myth, were home to countless monstrous creatures that would occasionally venture out to hunt on the surface and wreak destruction on settlements. Ancient tales also tell of the Vampires calling these caves home. 
By the formation of the early Final Kingdom, sometime before the First Free City, larger settlements had been established within the ancient abandoned fortresses across Sinderlan. From here, legends state that the people defended themselves from nightly raids originating from the Abyss. Eventually, the mythical King of Buried Nightmares ordered the sealing of as many Abyssal entrances as possible. However, ancient tales state that the most clever monsters of the Abyss were led by Vampires to continue regular hunts from the remaining entrances in the dark corners of the continent.

The Hunt of Chipped Fangs

Centuries later, legends tell that after the War of the Starfall, the Velnorclast led to subsequent ecological destruction and civil unrest across Sinderlan. Additionally, the monsters of the Abyss were whipped into a frenzy as the world burned around them while the Vampires quietly slipped into the shadows. The shattered south of Sinderlan caused multiple entrances to the Abyss to surface, leading to the south Kingdom being partially overrun with enormous creatures driven to violence. While the Queen of Reborn Doctrine established the Monarch's Bulwark to cleanse the Kingdom of civil unrest, she also allowed the reformation of the disparate leagues of Blood Hunters into the Hunter Guild of Sinderlan, geared at hunting down the Vampires and other "corrupted creatures" of Sinderlan. The hunters swept across Sinderlan in an inquisition that became known as the Hunt of the Chipped Fangs in 1567, in which they massacred any individual suspected of being a Vampire.
Legends state that their hunt was so brutal that it wiped out entire settlements in the name of order. During their hunt, they made their way into the Abyssal Reach, swarming the tunnels for years. They incorporated swords made from shattered remains of Velnor to cleanse the magical darkness from its deepest chambers. It is said that the hunt ended with the slaying of the last Tarrasque in the deepest chamber of the Reach. The legendary figure who landed the final blow was known to myth and history as Milothen the Cleanser. The hunters declared victory over the corrupted creatures, disbanding most of their forces on Sinderlan.
After the Hunt, the Abyss was left sterile and devoid of life. Its upper levels were used by some Kingdom and Didacy members as a means to escape the years of destruction that the Starfall caused, but were quickly vacated after the ecology of Perradin began to stabilize. After the recovery of society, many left the Abyss to its own devices, as it became inhabited by small animals and plant life. The deepest levels remained bathed in perpetual magical darkness, leading to very few attempts at exploration outside of resource searches.

Millennia of Vacancy

Occasional veins of minerals were discovered over the centuries in upper tunnels, but none that warranted large scale mining. Expeditions that tread deeper were perplexed by the fact that aside from some common mineral deposits, very few resources of note were ever found. Other more adventurous groups would venture into the depths in search of remnants of the Hunt such as broken weapons or fossilized remains, but were also met with little to no results. Archaeologist, paleontologists, and geologists have found the Abyss confounding in its nature, leading to folk tales of dark spirits still inhabiting the deepest chambers. This is furthered by the fact that many who venture into the tunnels experience headaches, nausea, and bouts of irritability for inexplicable reasons. Some have reported seeing remnants of strucures in the caves, but these have been attributed to delerious hallucination.
Over the years, occasional untouched chambers are uncovered, containing isolated ecosystems of monstrous creatures. These are usually uncovered during mining or construction projects. While the creatures within are dangerous, it is widely accepted that they are the lesser of the creatures that once inhabited the darkest depths of the Abyss. Typically, Blood Hunter freelancers or Bulwark members are contacted to subsequently "cleanse" the chambers, after which they are usually resealed. In rare circumstances, cleansed chambers are converted into something by their discoverer. The Briggand in the Basement Inn is actually constructed entirely inside a chamber, just outside the town of Clifract. The Limton-Bass Mine also has a cleansed chamber incorporated in its mining tunnels. Such locations have a reputation for being haunted to some degree.
The most recent expedition was in 9001 by the Clesmont Explorer's Club which descended into an entrance in the Kol Horn Mountain Range near the Tarburland village of Nostonta. After mapping roughly 8 miles of tunnels into the mountains, they returned to the surface with only one artifact: an ancient spear head fashioned from jade. The expedition disbanded shortly after, but Tarburland urban legends state that all of the adventurers died in mysterious accidents and illnesses over the next few years. The jade spear head was sold to an anonymous bidder at an estate sale of the last known member of the expedition to die in 9009.

Alternative Name(s)

The Reach, The Abyss, The Dark Place

Type

Cave System

Location under

Sinderlan