How Far in the Future is Urth?

People seem to have significant differences of opinion as to how far in the future Severian's Urth is. Is it a few thousand years in the future or a few hundred million? I lean toward one million years for these reasons: 1. The moon has been irrigated and now supports vast forests. Changing a barren rock into a place that supports life would take a long time. 2. Mining is done by digging up forgotten buried cities. 3. At some point in Claw, Severian climbs down a cliff, passing by layers of sediments that must have taken ages to lay down. 4. Enough time has passed for star-faring civilizations to have arisen and fallen. 5. Against the idea of hundreds of millions of years having passed, I would point out that there are still seven continents. And North and South America seem to still be in the same relative positions. However, I could change my mind if people have evidence for longer or shorter periods. Best wishes, Jack

The forested moon has to be superscience or an illusion or a deliberate fake, there being no other way to keep air on such a small body. none of the three are time-critical.

Today we are digging up artifacts from colonial era residences contemporary with the 17th century British trade in Roman artifacts left there in the time of Caligula, who helped himself to Alexander's breatplate, who helped himself to the gold of Egypt, which was perpetually being buried with pharoahs and then grave-robbed back into circulation for thousands of years before that.

landfills typically take a few decades to fill

Arguably it never fell, but may have moved around as different planets began and ceased to offer an incentive to trade - since Jonas was immediately familiar with Inire's Yesodi technology, we have no way to know if his many "normal" space journeys were sequential or not.

Clearly not forgotten, but just before the current economic crisis, the price of metals was high enough that people were starting to bandy about mining the land fills as cost effective Jeff

This already happens, except that it's even cheaper to dump the junk out on the ground in China where entire villages subsist on what they can sift out, instead of letting it be buried to begin with.