Antrim Coastal Drive

Running along Northern Ireland's coast, the Antrim Coastal Drive goes past all the major coastal attractions in the country, and, if you continue to follow the A2, all the way to the walled city of Derry on the border. 
Tucked under limestone cliffs with the sea crashing a few feet to the right, Antrim Coastal Drive is a particularly popular route in the summer months. On the drive, you'll go through the Nine Glens of Antrim — famous for their hiking opportunities, through the Mourne mountains, past 12th century Carrickfergus Castle, Carrick-a-Rede Rope Bridge, the beachside town of Portrush, coastal hamlets like Ballygally, Glenarm, Carnlough, and Waterfoot, and, most famously of all — the Giant's Causeway. And there are plenty of Irish pubs, harbors, and beaches you can stop by along the route, too. 
Designed by civil engineer William Bald and built between 1832 and 1842 to open up the glens for trade, before then it was actually easier for traders to make the short sea crossing to Scotland buy and sell, than to travel by land to the nearest market town. 

Practical Info

To join Antrim Coastal Road from Belfast, take the A2 for 22 miles north to the town of Larne—this is where the Antrim Coast Road officially begins. A two-lane road for the most part, drivers, cyclists and walkers should take care, as there are no bike lanes and footpaths are rare.