Google Directions traversal-time archive — UIUC campus OD pairs (Apr 23 – Apr 29 2026)
60-second polling of the Google Directions API on 8 fixed origin-destination
pairs across the UIUC campus, intended for transit-corridor traversal-time
analysis under varying pedestrian and traffic load.
Window: 2026-04-23 ~22:00 UTC → 2026-04-29 23:42 UTC (~5 days live data).