I built a coastal city far from my (coastal) capital, and I built the Harbor improvement in the new city, but I didn't get the trade route. I don't have a Harbor in the capital itself. Is this why? That is, does the capital have to have a Harbor too?

Incidentally, I learned the hard way that railroads give a hammer bonus only to the non-capital city connected to the capital, not the capital itself. :(

Is this why?
Yes.

Harbors only connect to other harbors. So for example, to connect intercontinental, you need a harbor on both continents, and then each harbor must also connect to the road network.

Thanks. Also, do you get a trade route if you connect (by road or harbor) a puppet city to your capital? I haven't tried it yet.

Yes, you do.

Thanks very much. :)

Incidentally, I learned the hard way that railroads give a hammer bonus only to the non-capital city connected to the capital, not the capital itself. :(

This just doesn't quite seem right to me. I think the capital should get it as soon as it's connected to any other city.

Agreed. I was very annoyed to find this out as the Iroquois, as my Capital had a huge amount of forests and ended up being my production city.

Thanks. Also, do you get a trade route if you connect (by road or harbor) a puppet city to your capital? I haven't tried it yet.

Yes. And puppets seem to like building harbors, so if you just connect one of your coastal puppets to your trade network, they'll usually all end up in it fairly quickly.

This just doesn't quite seem right to me. I think the capital should get it as soon as it's connected to any other city.

So under the current version, there is no way to ever get the RR bonus in your capital, only the other cities? Laaame.

Harbor-Harbor makes sense -- that explains why my advisors were constantly nagging me to build harbors even though the cities were already connected to the capital via road.

It was still silly, though. The advisors want a harbor in every coastal city ASAP...not worth it for 3GPT

Just by reading the tooltip of the harbor, it doesnt say that you need to have a harbor in your capital as well to make the trade route connection.
Until i saw this topic i thought that the harbor is bugged and doesnt give a trade route.