I lived in Dunedin for three years before I came across the beauty of Tunnel Beach. As soon as I discovered it, I more than made up for the oversight, spending hours enjoying its glorious landscape. Now, having moved on from Dunners, the beach always near the top of my list when I return.
A 10-minute drive from Dunedin city centre, along Blackhead Rd, there's a dead-end turn signposted to Tunnel Beach Road. Before leaving your car roadside (because the road is also the carpark), make sure your backpack has everything you might need for a couple hours. Having once lugged down a quiche lorraine in a ceramic dish, I recommend you pack light, and essential.
At the start of the path you'll see spectacular views - nothing but the sea beyond. Panic and doubt might snatch at you because it looks as if the cliff face just drops away. But behold, you're not going abseiling - the walk down is manageable on a wide gravel path that hand rails in places. Winter will give you mud and summer will give you dust, so make sure you have appropriate shoes. The views on the way down will take your breath away and you'll find a lot more than just beach before you.