The backbone lanes · a structural model

Route Persistence
1550 – 1815

The trade lanes that recur most across the age of sail — each port's principal routes, activated in the decades that port ranked among the ten busiest, then ranked by staying power.

Structural, not empirical. The lanes are each port's genuine principal routes; but there is no historical record of ranked top-ten routes per port per decade. A route counts as "active" in a decade when its origin port sits in that decade's combined top ten (ship-count + tonnage + value) and the decade falls inside the lane's era. Max = 27 decades.
#RouteCargoDecades activeDec.Span
Compiled for the Idle Sails project · a structural trade-lane synthesis over the per-decade combined top-10 ports · 27 ports · 165 distinct lanes from 1,818 port-decade route entries · data: research/route-persistence.csv & routes-by-decade.csv