Tiwanaku/Pumapunku: Precision Andesite Engineering at 3,800m Altitude

Pumapunku: 167×117m terraced platform
Akapana pyramid: 257×197m base, 16.5m height
At 3,800m altitude beside Lake Titicaca
Population: ~20,000 in urban center

Perimeter drainage channel around ceremonial center
Surface canals + SUBTERRANEAN channels connected
to perimeter (MDPI Water, 2020)
Rainfall collection reservoirs
Deep groundwater aquifer management
Lake Titicaca: massive adjacent water body
(8,372km², max depth 281m)
Water used to stabilize foundations and prevent
subsidence beneath monumental structures

Andesite: volcanic rock with quartz content
Red sandstone: quartz-bearing (confirmed)
Pumapunku stones cut to SUB-MILLIMETRE precision
Largest single stone: 131 tonnes
If acoustic technology requires precise coupling
between stone interfaces, this level of precision
is a DESIGN REQUIREMENT, not aesthetic choice.

Collapse ~1100 CE coincides with Lake Titicaca
level drop due to drought (Binford et al.)
Paleolimnological records confirm abrupt climate
change at time of collapse.
Fifth site where water failure = civilization fall.

suggesting acoustic function, cohesion, decline=water).