The Lost Capital is the former seat of the ancient Rhodesian Empire.
At its peak the capital was about 100 miles across, similar to modern day Paris and surrounding area in size. The outermost wall lies in ruins, and the areas within it are often little more than rubble that's often picked over already and/or home to bandits with nowhere else to hide.

Assuming the bandits or crusaders don't get you, you'll reach the inner ring. This is a more dense, walled area of the capitol. This ring wall is much more intact, mainly because it keeps the rot plague in as much as it keeps intruders out. Past the ancient gates you'll find a lot more rewarding loot, but also a lot more danger. Rot plague nests can be found here, as do the magically imbued defenders of old. They take a few different forms: Enchanted statues, beings made of elemental energies, even the occasional automatons. All are deadly to the unprepared. Naturally surviving these hazards can reward you with more than enough riches to become landed, but you'll still to make the trek home safely.

Finally, should you overcome all of those obstacles you'll reach the White-Gold Palace. This magnificent edifice is the ancestral home of all of the great emperors of the old empire. Legend says that it was built by the first Emperor Valkorian, but only after he spent 5 years toiling and building homes and infrastructure for his people as a common laborer. This resplendent fortress appears untouched by time or the plethora of dangers that surround it. Powerful magic inhabits the very walls, and the interior has never been successfully mapped as things seem to shift and change each expedition. Many dangers lurk within too, but they too are poorly recorded beyond mention of horrors, traps, and wonders of a terrible nature. What is certain is that only the greatest heroes of the age can hope to brave its halls and return alive.