Trails: Whilst most tourists head straight for (and only do) the Waterfall Trail, as a frequent wanderer on these trails my advice, if you have time, is to get higher up within the park, the views of the glen are well worth it.
The Waterfall Trail: Start at the carpark and follow the path heading back towards the entrance of the park, the ways are all well signposted. This will snake back on itself as you move down to the river where the water roars (at this time of year anyway) over waterfalls as it makes its way to the sea. A wooden walkway allows you to get up close to the beautiful views of the falls, pools and greenery. The path then starts to climb and will return you to the car park just below the cafe.
The Scenic Trail: (with plenty of waterfalls of its own...) Go Up! Start in the carpark and follow the path in front of the cafe and shop, (closed off season) stay right on the path (ignoring some signs) it will take you past a pavilion/rain shelter, here take the left fork and follow the path along the Inver river up to where it falls into the valley. At the top you can rest a moment in a little shelter and take in the stunning views of the Glen, the sea beyond and on a good day, Scotland across the way. Just past the shelter you can decide to take a route which will cross the river and climb higher still or continue the loop back to the Car Park and the start of the Waterfall Trail.
To go higher, take a left just past the hut and, keeping left, follow the path down to where it crosses the river between two waterfalls, then simply follow the path up to the tree line at the highest point in the park, offering you stunning views of the Glen bellow, the bay and Trostan mountain just slightly to the West. The trail then makes its way back down into the Glen and will eventually re-cross the river where you can take a right to retrace your earlier steps to the cafe.
To loop back, simply stay on the main path beyond the hut and keep left at a sign posted fork, this will take you high above the carpark and allow you those continued views of the bay. You’ll cross the entrance and exit roads as you make your way down, so be wary of traffic, before joining a part of the trail which follows the river as it dramatically makes its way across the valley floor, leading you to the start of the Waterfall Trail.
If you have time, and daylight, when you're leaving the park head down to Waterfoot beach. Simply take a right when leaving the park and follow the road down to the shore, take a right over a bridge into Waterfoot and the beach is a sharp left between the houses. (It is signposted but don't drive too fast least you miss it!) It offers beautiful views out towards Scotland and the towering Glen above. To the left of the beach you'll see some caves which were once homes, one belonged to an old woman who charged tourists for the "healing" water from a waterfall nearby (and gave them her home brewed Poitin for free...). There's also the ruins of a castle, destroyed by Oliver Cromwell's troops, and often a rather playful seal in the bay. It's an often missed spot on our Causeway Coast and I like to add it to my Glenariff walks when I have the time.