The map tiles are cached and served from our CDN with over 140 edge servers (POPs) on 5 continents. Minimal latency is ensured by selecting the geographically closest server to the visitor by IP anycast service based on the actual user location.
There are two fully redundant and automatically replicated core data centers in Western Europe and North America serving the map data. Each datacenter can run the map tile service independently, but usually, they are operated simultaneously and the traffic is split between them with geographic preference.
In both datacenters, we deploy a high-availability setup, with a load-balancer actively triggering health checks and setting up failover to additional machines. The infrastructure is scalable - additional machines are launched to handle increased traffic and peaks.