The map and the diagram are drawn by your browser from four calls made while you look at the page: the edge tells which data centre answered you, the Worker tells which bindings are on, a measurement shows where the D1 database and the two Durable Objects live, and the counting works show where today’s guests came in. No IP address, city or cookie is stored.
The edge
The page is built in whichever Cloudflare data centre is closest to you. The same data centre runs both Workers; the call between them is a service binding that never touches the internet.
D1
The database has one primary copy in a particular place. The answer shows the region (e.g. WEUR, western Europe) and, when Cloudflare reports it, the data centre and whether it was the primary or a replica.
Durable Objects
The thing meeting and the stool are each one object that lives in one place: where it was first used. Every guest is connected there. The object finds its own data centre by asking Cloudflare where its own call left the network.
What is not measured
Workers AI, AI Gateway, AI Search, Workflows, Queues and Browser Run are not called by the map, because they cost money or take time. They show as on when the binding exists in the Worker right now.