Though Northern Ireland may not look that big on paper, tackling a fair share of its many attractions in less than a week isn't possible without exhausting yourself in the process. If your time is limited, choose the eastern half (Belfast, the Antrim Coast, and the Mountains of Mourne) or the western half (Derry and the Border Counties). The cities are small enough to tackle in a day or two. But remember that the rural wonders—the Antrim Coast, the Fermanagh lakes, the Mountains of Mourne—cast their spell easily. You may head out to enjoy them for a day trip and find yourself wishing that you'd factored in more time to explore the endless string of postcard-worthy villages, misty glens, and rugged mountains. And although distances are not great, neither are the roads—you'll spend most of your time traveling smaller roads, not major express highways.