Do nuns ever get to go out?

Yes!

The great Moniales OP blog (by the Summit, New Jersey Dominicans) is running a series on "Debunking Cloister Myths."

Here's part of the first one:

MYTH #1
CLOISTERED NUNS NEVER GO OUT....
as in never go out of doors and never go out of the enclosure.

If it never dawned on you that people think that cloistered nuns never go out of doors within the monastery gardens, well, you'd be amazed at how many people, including "devout" catholics think this is true. It's not unusual for a group of kids from a local school or bible camp to come full of questions. One little kid raises his hand energetically, "Sister, Sister, do you go out?"
Sister: "Do you mean outside in the garden?"
Little Tyke: "Yeah!"
Sister: "Why of course! We love going outdoors in the garden. We have flower gardens and vegetable gardens and paths for walking. In the winter we even go sledding. Some of like to make our medition out side, contemplating the beauty of God's creation. It's even fun to walk in the rain! In fact the cloister garden was traditionally called the "Paradise" because it was supposed to be reminder of the Garden of Eden."

The rest of the post, which you can find here, mentions that the sisters are also allowed to go out for doctors appointments, to visit home if their parents are ill and can no longer travel, or for the occasional meeting.

As you can see from this wintertime photo, the "Monastery Gardens" are not some little plot of land. I think "Garden" should be taken in more of the English countryside sense ...