Simplifying the thousands of VPCs, subnets, routes, etc you may have.

https://aws.amazon.com/blogs/aws/new-use-an-aws-transit-gateway-to-simplify-your-network-architecture/

Note: currently only available in:

• US East (N. Virginia)
• US East (Ohio)
• US West (Oregon)
• US West (N. California)
• Europe (Ireland)
• Asia Pacific (Mumbai)