These are the routes associated with VPC vpc-hydra.
The five default routes were created automatically when the VPC was created. The other three routes were learned via BGP from AWS Virtual Private Gateway.
The subnet 172.16.0.0/16 was learned via two different VPN gateway tunnels from AWS region eu-west-1. Both routes were installed on the routing table since their costs (priorities) are the same – 100. The subnet 172.18.0.0/16 was learned only via one VPN gateway from AWS region us-east-1.
The next hop IP addresses are for the default routes are towards the GCP VPC or internet gateway.