The Pony Pens sit about eight miles along NC 12 from the Ocracoke Visitor Center. The parking area has auto and bus/RV parking, plus a picnic table; a restroom is listed, though public restrooms may be seasonal and their type isn't clear. Accessibility is noted for the site, but available details don't spell out whether both raised decks or the full boardwalk are accessible, so check current information if that matters for your visit.
Give the first deck a few minutes, then decide whether you want the farther one. If the horses aren't out, the beach access is nearby. They can be seen throughout the year, but being in the enclosure doesn't mean they'll be visible whenever you stop.