Three-tier AWS web application architecture distributes traffic through CloudFront CDN to an Application Load Balancer spanning multiple availability zones. The ALB routes requests to EC2 t3.medium instances in Private Subnet 1, which connect to an RDS Primary db.t3.medium database with a Read Replica in Private Subnet 2 for improved read performance and disaster recovery. This pattern demonstrates AWS best practices for high availability, fault tolerance, and separation of concerns across presentation, application, and data tiers. Fork this diagram on Diagrams.so to customize instance types, add auto-scaling groups, or integrate additional AWS services like ElastiCache or S3. Perfect for documenting production architectures or planning infrastructure-as-code deployments with Terraform or CloudFormation.