Mines of Tethyamar

Fictional record. This page describes a mine from a fictional setting, not a real place. Information is based on the cited canon, with adaptations and interpretation distinguished where necessary. It is kept separate from the real MineArchive corpus — see Fictional.

Setting	Dungeons & Dragons (Wizards of the Coast)
Location	Beneath the northern Desertsmouth Mountains in north Faerûn, on the eastern edge of the desert of Anauroch, about 350 miles north-north-east of Eveningstar and beyond the Storm Horns; its riches went down the River Tesh to the Moonsea.
Type	Metal ore (dwarven)
Worked	Founded in the Year of Depths Unknown, −145 DR, by Roryn of the Iron House. – Lost to the Great Hlundadim's orcs and goblins after a decade's resistance; an upper fortress reopened by the Zhentarim by the late 15th century DR.
Extent	Very deep, following long vertical veins of ore, with chains of chambers along them; the design spread the hold over a far greater extent than other dwarf holds.
Controlled by	The Iron House of Tethyamar (From −145 DR to the fall), Zhentarim (Late 15th century DR)

Overview

The lost dwarven mines of the Desertsmouth Mountains, founded by the Iron House in −145 DR along deep vertical ore veins, rich enough to trade with half of north Faerûn, and overwhelmed by orcs, goblins and demons after a decade's siege; a name adventurers have followed underground for a generation.

History

Tethyamar was founded in the Year of Depths Unknown, −145 DR, by Roryn, blood of Thordbard, of the Iron House of fallen Oghrann. Generations of dwarves carved halls along the ore veins under the northern Desertsmouth Mountains and sold what they dug and forged to the human and elven realms around them, first Anauria, Asram, Cormanthyr and their neighbours, later Cormyr, Myth Drannor and the Moonsea towns, sending rafts of riches down the River Tesh. The hold was beset by orcs, hobgoblins and ogres from the start, briefly fell to orcs of the Dragonspine Mountains and was retaken, and afterwards sponsored the fortress-city of Rulvadar to guard it.

Its trade prospered until the founding of Flostren's Hold in 747 DR; once that place came under the Zhentarim, the two mining nations were rivals. Tethyamar's scattered design, chambers strung along descending veins rather than gathered in one fortress, made it hard to defend, and its dwarves were hardier and more self-reliant for it; clan mattered less there than being a Tethyamar dwarf.

The end came after more than a decade of resistance, when a legion of orcs and goblins with barghests and demonic allies, led by the self-proclaimed Great Hlundadim, overwhelmed the hold. The surviving dwarves of the Iron House fled to the Far Hills and the Storm Horns of Cormyr; of the royal family only the king's youngest son, Ghellin, lived. A later attempt by Borlin's Mithril Legion to retake the mines was defeated, Ghellin died in exile of a wasting disease, and the dwarves of the Sea of Fallen Stars went on saying that the king would take his throne again. By the late 15th century DR the Zhentarim under Kara Chermosk held one of the upper fortresses and had reopened mining there.

Workings

Chains of chambers (housing, forges, tombs and storage) built along the long vertical ore veins the dwarves followed down, so that the hold descended with its mines rather than sitting above them.

Real-world mining concepts used here: Vein

Closure

Conquest: a decade's war against the Great Hlundadim's orcs, goblins, barghests and demons, ending in the hold's fall and the flight of the Iron House.

What became of it

A ruin held by orcs and worse, with the Zhentarim mining again from an upper fortress by the 1480s DR; the Dungeons & Dragons Online adventure pack The Mines of Tethyamar sets a drow expedition there in 1487 DR.

Canon & adaptations

The Forgotten Realms Wiki's account draws on both the campaign sourcebooks and Dungeons & Dragons Online; the online game's outpost and its drow of House Argith are the adaptation's additions to the older sourcebook history of founding, trade and fall.

Recorded claims

Each claim is marked with its basis — explicit canon, MineArchive inference, adaptation only, or fandom interpretation — and attached to the source(s) below. Where tellings disagree, both are kept.

The mines of Tethyamar, beneath the northern Desertsmouth Mountains, were once home to one of the greatest dwarven communities of north Faerûn. (explicit canon) ^1,2
The mines followed long vertical veins of ore, with chains of chambers for housing, forges, tombs and stores strung along the descending veins, which made the hold far more spread out than other dwarf holds. (explicit canon) ^1,2
Tethyamar was founded by Roryn, blood of Thordbard, of the Iron House of fallen Oghrann, in the Year of Depths Unknown, −145 DR. (MineArchive inference) ¹
Its ore, metalwork and riches went down the River Tesh to the Moonsea and beyond, and it prospered until the founding of Flostren's Hold in 747 DR brought competition under the Zhentarim. (explicit canon) ¹
After more than a decade of resistance Tethyamar was overwhelmed by orcs and goblins with barghests and demonic allies under the self-styled Great Hlundadim; the survivors of the Iron House fled to the Far Hills and Storm Horns of Cormyr. (explicit canon) ¹
Borlin's Mithril Legion failed to retake it; by the late 15th century DR the Zhentarim under Kara Chermosk held an upper fortress and had reopened mining. (explicit canon) ¹

Sources

(interpretation) Tethyamar — Forgotten Realms Wiki — Forgotten Realms Wiki (Fandom)
(adaptation) Tethyamar Mining Outpost — DDO Compendium — DDO Compendium

Record created: 24 October 2026 · Last researched: 24 October 2026