What exactly you mean by "cascade"? A "climbing" rose?
For start, I suggest browsing the "Help Me Find Roses" website, just to get an idea. You can also access nurseries that specialize in roses and check their stock.

If by cascading you mean climbing (and just not tying it up so the canes droop naturally,) have you ever seen Zephirine Drouhine? http://www.helpmefind.com/gardening/l.php?l=2.2572

I probably sound like a broken record, but I adore this rose - I live pretty much on the cusp of 5/6... it grows fast, isn't terribly prone to disease, smells heavily of old roses (especially when its humid,) and blooms in flushes all season long. Plus its pretty much thornless, which makes dealing with the long canes easier.

...basically I love this plant.

Lothlin, I noticed your love and was even considering it. However, some folks warned me about black spot. Others complained Zephirine Drouhine's recurring blooms are weak. Is that true?

mmmm I notice a little black spot on mine if it stays really damp for a while, but generally its not bad and I usually don't have to spray it. I've got mine planted on the south-facing wall of my house, so it does get prime sun, all day long. As far as weak recurring blooms goes, its hard to say, though mine has only been planted about three years now so its still not fully mature. That said, I always seem to get at least a handful of strong flushes, with a smattering of blooms in between the flushes, pretty much all summer long.

The flowers do seem to open up fairly quickly, so they ten to stay looking like this for most of the time they're blooming though. So not good if you like more of a hybrid tea form.

{{gwi:253754}}

It'll bloom in clusters to - so three or four flowers in a clump. Its seriously fragrant though, if that's a big deal for you - I'll be gardening and I'll be able to smell the plant from like five or ten feet away.

Maybe someone else will be able to weigh in with a different experience XD I seem to have weird luck with plants - I've also got a Snowfire plant that does amazing despite it being a notoriously bad plant for getting diseases.

Mike, by cascade I meant flowing over the sides. I will check our "help me find roses" website. We are a ways from nurseries so was trying to get ideas before making a trip to the city.
Lothlin, Zephirine Drouhine is beautiful and may just be what I am looking for. Do you buy yours at a local nursery or do you shop online? Thanks so much

I think ZD would be a good choice. I ordered mine last year from Roses Unlimited, it is already gigantic and is loaded with buds.

Thank you, Sara-Ann

I bought a grafted one from the local nursery, but if you want to order online, Rogue Valley Roses has own-root bands of ZD in stock. I've had a lot of success ordering from them.