A system and method for data route discovery through cross-connection tunnels uses routing configurations from a local edge router in a private cloud that include learnt and advertised subnets, as well as cross-connection tunnels for the learnt and advertised subnets, to populate a public cloud table of public cloud learnt subnets and a public cloud table of public cloud advertised subnets. The public cloud tables of public cloud learnt subnets and public cloud advertised subnets are applied to discover data routes through the cross-connection tunnels of the hybrid cloud environment.