After 9:00 PM · Night
The roads keep their promise
Late at night, the road network works the way the map says it should. From Diego Martin in the west to St. Augustine and the UWI campus in the east, the whole East–West Corridor sits within a half-hour of the hospital gate.
6:30 – 8:30 AM · Morning rush
The corridor closes
As the Beetham and the Priority Bus Route back up with the commute from east Trinidad, and the Lady Young descends into Morvant bumper to bumper, the catchment collapses to roughly a sixth of its nighttime size. San Juan is four kilometres away — and on a bad morning, it is no longer 30 minutes from the hospital. Neither is Barataria. Neither is the airport corridor.
11 AM – 2 PM · Midday
A partial recovery
Between the rushes, the map breathes again. The inner suburbs come back — San Juan, Barataria, Valsayn, Petit Valley — but the nighttime reach never returns. Even at its calmest hour, daytime Port of Spain gives you about half the catchment the night does.
4:00 – 7:00 PM · Afternoon rush
The smallest hour
This is the window commuters report as the worst of the day — Saddle Road backed up out of Maraval, the Beetham at a standstill, the Lady Young a parking lot — and the map agrees. The 30-minute zone shrinks to ~13% of its nighttime area, barely escaping the city bowl. At the exact hours when the roads are fullest of people, the hospital is effectively furthest away.
The four cities of Port of Spain
Same hospital. Same roads.
Four different cities.
Overlaid, the four catchments look like the rings of a tide going out. Nothing about the geography changes between 5 PM and 11 PM — only the traffic. The difference is a factor of ~8× in area.