Mermaid has been mentioned, and it's a beatiful rose but
it is recommended for south and west facing walls as it is not
that hardy. Also, it's a whopper, maybe too vigorous for a gate.

I have Zepherine Drouhin and Madame Alfred Carriere, and
though they are both as yet young specimens, I would say that
Madame A.C. is healthier ( Z.D. seems to suffer from rust, and
benefits from spraying, which is hard if it's out of reach ).
Madame A.C. also is not IME best pleased with rain, the blooms
suffering a little and going brown at the edges in prolonged wet
weather.

However, I am in the southwest, which gets a lot of rain and rust.
On a plus note, in this area Madame A.C. seems semi-evergreen.
Neither rose seems to be terribly rampant, so OK for a gate.

Andy