The Cliffs of Moher are the most visited natural attraction in Ireland and the one most likely to disappoint, entirely because of when people go and what they expect.
What they actually are
Eight kilometres of sheer sandstone and shale on the Clare coast, rising to 214 metres at the northern end. On a clear day you can see the Aran Islands and the Twelve Bens of Connemara. In fog you can see about nine metres, and the fog is not rare.
When to go
The visitor centre car park is busiest between eleven and four, and coach tours cluster around midday. Before ten or after four is a different place. In summer the light lasts until well past nine, so a late afternoon visit gives you low sun on the cliff faces and a fraction of the crowd.
The centre and car park close in the evening but the site itself is accessible; check current arrangements before relying on that.
The walk most people miss
The paved section around the visitor centre holds the majority of visitors. The Cliffs of Moher Coastal Walk runs about 20km from Doolin to Liscannor and you can do any piece of it. Twenty minutes north from the centre and the crowd thins to almost nothing.
Stay behind the walls. People die here most years, generally by climbing over for a photograph on ground that is undercut.
The boat alternative
Doolin boat trips run along the base of the cliffs and give you the scale in a way the clifftop cannot. They are weather-dependent and the sea is often lumpy. If you get seasick, this is not for you; if you do not, it is the better view.
Is it worth building a day around?
No. It is worth ninety minutes as part of a Clare day that also includes the Burren, Doolin and possibly the Aran ferry. Building a day around the cliffs means a lot of driving for one viewpoint that may be in cloud.
If you are based in Kerry rather than Clare, consider skipping them entirely. Slea Head and the cliffs at Kerry Head are emptier and the drive is better. The Cliffs of Moher are worth the stop and rarely worth the detour.
Practicalities
Parking is included in the admission charge and timed-entry booking online is cheaper than at the gate. There is no shelter on the cliff path. Wind is the real hazard, not rain; on a bad day the gusts come over the edge hard enough to move you.