Mercer Bay Loop is a short but dramatic coastal walk near Piha in the Waitakere Ranges, circling the headland above Mercer Bay to reveal some of the tallest sea cliffs in the Auckland region — at around 60 metres, the sheer rock faces dropping directly to the Tasman Sea are an impressive sight on a relatively accessible track. The 2.1-kilometre loop starts at the end of Te Ahuahu Road and takes 45–60 minutes, gaining around 173 metres of elevation with a few steep sections near the cliff edges. The area holds significance for Te Kawerau a Maki, the iwi of the western ranges, and dogs are permitted on lead.
Practical Information
| Location | End of Te Ahuahu Road, Piha, Waitakere Ranges |
| Distance | 2.1 km loop |
| Elevation gain | Approximately 173 m |
| Difficulty | Moderate — some steep sections near cliff edges |
| Time needed | 45–60 minutes |
| Parking | Small free car park at the end of Te Ahuahu Road |
| Facilities | No facilities on the track; toilets at Piha Beach (5 minutes by car) |
| Cost | Free |
| Dogs | Permitted on lead |
| Drive from Auckland CBD | Approximately 50 km via SH16 and Scenic Drive; allow 50–60 minutes |
About the Walk
The Mercer Bay Loop packs considerable drama into a short circuit. From the car park at the end of Te Ahuahu Road, the track rises quickly through coastal scrub and regenerating bush before opening onto the exposed headland above Mercer Bay. The cliffs here drop around 60 metres directly to the Tasman Sea — among the tallest sea cliffs in the Auckland region — and the views along the coast in both directions take in the rugged character of the Waitakere coastline in a way that is difficult to access anywhere else without a much longer walk.
The loop follows the clifftop for a section before descending through bush and returning to the car park. The path is clearly marked throughout, though some sections near the cliff edges are narrow and exposed. The track is not fenced at the edges — caution is required, particularly in wet conditions when the ground can be slippery. The elevation gain is moderate but concentrated, with the steepest sections occurring early on the ascent.
Mercer Bay below the cliffs is visible from several viewpoints along the track — a small, sheltered bay with turquoise-tinted water that is inaccessible by land. The bay takes its name from an early surveyor of the Waitakere coastline. The contrast between the flat, calm-looking bay far below and the exposed headland above reinforces the scale of the cliffs.
Kauri dieback disease is present in the Waitakere Ranges, but the Mercer Bay Loop sits outside the primary kauri forest areas — boot cleaning stations may not be present at this specific trailhead, though it is always good practice to clean footwear before and after any Waitakere bush walk.
Te Kawerau a Maki — Significance of the Area
Te Kawerau a Maki are the mana whenua of the Waitakere Ranges and the western Auckland coastline. The Waitakere Ranges — Te Wao Nui a Tiriwa, the great forest of Tiriwa — have deep cultural and historical significance for the iwi as a source of food, timber, and rongoā (traditional medicine). The coastline around Mercer Bay and the Piha area was used for fishing and as a route between the western coast and the Waitemata. The area is protected under the Waitakere Ranges Heritage Area Act 2008, which recognises both the ecological and cultural importance of the ranges. Visitors are encouraged to treat the landscape with respect as a significant cultural site.
What Visitors Say
AllTrails reviewers consistently praise the Mercer Bay Loop for delivering impressive coastal scenery in a short time frame — the sea cliffs are frequently described as unexpectedly dramatic, and walkers note that the views reward the moderate elevation gain disproportionately. Several reviewers recommend combining the loop with time at Piha Beach in the same visit.
Google reviewers highlight the short drive from central Auckland and the quality of the clifftop views as reasons to make the trip. A few walkers mention that the car park fills quickly on fine weekends — arriving before 9am or after 3pm is often advised to secure a space.
Where to Learn More
Auckland Council — Waitakere Ranges Regional Park — official park page covering tracks, access information, cultural significance and visitor guidelines for the Waitakere Ranges, including the Piha and Mercer Bay area.
AllTrails — Mercer Bay Loop Walk — trail map, elevation profile, user photos and current reviews from walkers, including recent notes on track conditions and car park availability.
Waitakere Ranges Heritage Area — information on the Waitakere Ranges Heritage Area Act and the cultural, ecological and landscape values that define the western ranges and coastline.
Frequently Asked Questions
Where is the Mercer Bay Loop?
The loop starts at the end of Te Ahuahu Road near Piha, in the Waitakere Ranges — approximately 50 kilometres west of Auckland CBD. Allow 50–60 minutes driving time via SH16 and Scenic Drive.
How long is the Mercer Bay Loop?
The loop is 2.1 kilometres and takes 45–60 minutes to complete.
How hard is the Mercer Bay Loop?
The walk is rated moderate. It involves around 173 metres of elevation gain and some steep, narrow sections near the cliff edge. It is suitable for reasonably fit walkers; not ideal for very young children or those with limited mobility.
Are dogs allowed on the Mercer Bay Loop?
Yes, dogs are permitted on lead on the Mercer Bay Loop Track.
Is there parking at the Mercer Bay Loop?
Yes — there is a small free car park at the end of Te Ahuahu Road. It fills quickly on fine weekends; arriving early in the morning or late afternoon improves your chance of finding a space.
What are the sea cliffs like at Mercer Bay?
The cliffs above Mercer Bay are approximately 60 metres high — among the tallest sea cliffs in the Auckland region. They drop directly to the Tasman Sea and are visible from several exposed viewpoints along the clifftop section of the loop.
Is the Mercer Bay Loop free?
Yes, the track and car park are both free to use.
Can I combine the Mercer Bay Loop with Piha Beach?
Yes — the Mercer Bay car park is a five-minute drive from Piha Beach. Many visitors combine both in the same trip.
For more walks across the region, see the full guide to walking tracks in Auckland. The summit at Maungawhau / Mount Eden offers a very different experience — a short volcanic cone walk with city and harbour views from the top.