Containers for climbers needs to be deep, deeper the better and at least 2 feet deep x 2 feet wide as roses have extensive roots. You might struggle to find a rambler to suit for a pit due to the size they grow to and big root system. I've just planted New Dawn rose ( light pink and scented) in a north facing position in a container as this can cope with shade and has repeat flowers. Also just potted up a Gertrude Jeykell rose for the same reason ( deep pink, repeat flowers and a heavenly scent) but this may need more sun than north facing gives. I'd recommend you Google climbing roses for containers in north facing position. This will give you some good options. Because roses generally lose their leaves in winter, I've planted one of mine with an evergreen clematis called Early Sensation but their are others. Happy gardening