Where can I find an API with information about air, rail and ferry routes?

Question

API

Hello!
Please tell me the service through the API of which you can get information about the maximum possible number of air, railway and ferry routes.
Actually the essence is simple. There are 2 cities and you need to determine if there is an air, railway or ferry service between them.
I'm looking for a free or not expensive API.

Answer 1

Most likely it will be necessary to use different providers or service providers.