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Currently, Orakei Korako (The Place of Adorning) is the geothermal site featuring the highest number of naturally active geysers in New Zealand. The Waikato Regional Council Technical Report 2020/04, Sinter-forming springs and geysers of the Waikato region by Cody, Keam, Lebe, Lynne, and Luketina, states more than 35 active geysers in the past decade. US geyser expert T. Scott Bryan saw ten geysers erupting during his visit in 1993 (GOSA Transactions V, 1994).
My personal impression is that especially on Golden Fleece Terrace and on Artist's Palette geyser activity is shortlived, so many of the listed geysers may never play again. Therefore, at any given time the count must be assumed to be clearly less than thirty and, currently, most probably even less than twenty. It can not be ruled out, though, that some of the geysers are only longterm dormant due to an exchange of function with others.
On our visit on 21^st November 2019, we observed five geysers playing, four perpetual spouters and some intermittently upwelling springs. Presumably, this is what you now can expect to see when strolling some hours over the public boardwalks. Besides the geyser spectacle we got the impression that Orakei Korako was the most colourful geothermal area on our New Zealand trip.

Although Orakei Korako is located only 25 km (15.5 mi) north of Taupō, so far it has not become a tourist hot spot. Waipapa Valley, the publicly accessible site, is only a small part of the whole geothermal area, which extents 3.3 km (2 mi) on either side of the Waikato River and includes in southern direction also the Red Hill area, where Hot Waterfall Geyser is located, as well as a small geyser on the west bank of the river. Before the water level of the river in Waikato Valley was raised by 18 m (59 feet) in 1961 for the sake of hydropower development, the valley hosted at least 105 geysers and more than 1000 hot springs in total (Lloyd, 1972). Among the 70 flooded geyseres were Minginui Geyser, as second largest geyser of New Zealand once observed playing 90 m (295 feet) high, Orakeikorako Geyser, which reached up to 55 m (180 feet), and Rahurahu with a height of up to 40 m (131 feet). Porangi Geyser was the largest frequently erupting geyser and spouted to 24 m (79 feet).

With a little luck you may spot the first geyser playing even before you have crossed Lake Ohakuri by ferry boat. On the ridge at the righthand side above the visible sinter terraces the large eruption column of Kurapai Geyser often skyrockets 6 m (20 ft) high, but also 10 m (33 ft) bursts have been recorded. During our visit it played approximately every hour for about three and a half minutes. Its intervals are described as irregular, though, ranging from 35 minutes to months of dormancy. It has to be noted that the geyser is not of natural origin but was created in 1961 by forcing a steel pipe into the vent of a hot spring, what explains the slender eruption column. Before the manipulation, the periodically surging spring was known as Bendix Washer by reference to the name of a popular washing machine.

Kurapai Geyser is not accessible to the public because the cliff is too dangerous. Approximately 5 m (16 feet) west of Kurapai the Ellan Vanin pool is located, for which I was unable to find evidence of geyser activity.

According to Jeremy M. O'Brien even on the west side of Lake Ohakuri beyond the parking lot thermal pools are present such as Map of Australia, Green Pool, Brown Pool, Bracken Pool and Utility Pool. But it should be noted that the area is closed to the public. From the visitor centre groups and also individuals are ferried on demand across the sheltered Lake Ohakuri to the jetty near Emerald Terrace.

Kakariki (which means "green") or Emerald Terrace now is one of the largest sinter terraces of New Zealand above water level, whereby it continues 35 m (115 feet) under the lake. Today it serves as the first step on the way into the Orakei Korako thermal area. Emerald Terrace got its name from the green algae which thrive in the extensive films of somewhat cooled thermal water. Close to the lake and on the far side of the terrace, as seen from the boardwalks, the Emerald Fault cuts in north-west direction through the northern corner of the terrace. Like all other faults at Orakei Korako it was formed in 131 AD by a strong earthquake in the course of the Taupō eruption and still powers geyser activity. Near the spot where the fault leaves the sinter area to the northwest Aorangi Geyser played up to 15 m (50 feet) high in the 1960s (R.F. Keam, 1965).

While in the strict sense a terrace is the area above a rising step, at Orakei Korako often the fault scarps and the areas immediately below and above are described as parts of the same terrace. So in the west of Emerald Terrace the boardwalk marks the border to the Rainbow and Cascade Terrace, which is terminated further west by the steep Rainbow Fault Scarp. Although the official name is Aniwaniwa - Rainbow and Cascade Terrace, commonly the southern section or sub-terrace is called Cascade Terrace and the northern one Rainbow Terrace.

Diamond Geyser, famous for the ejection of numerous sparkling water droplets during the eruption, is the first feature of Cascade Terrace you come across if you follow the boardwalk uphill. Its Māori name is probably Potiki, which could be translated as Youngest Child or Pet. With eruption heights of usually 2-3 m (6-10 feet), occasionally even up to 8 m (26 feet) and, at least in the past, intervals as short as 20 minutes, Diamond Geyser is regarded as the main geyser of Orakei Korako in recent time. However, on our visit the geyser cone was embedded in strongly sprouting bushes with undamaged leaves, hinting that the last eruption must have been already long ago. And indeed, my investigations indicated that Diamond is dormant probably since 2005.

Already from the boardwalk the geyser cone appears to have a complex geometry. This impression is confirmed by a look into the orifice, something that is not possible for ordinary visitors. Diamond's cone consists of three pools. The 3.7 m (12 feet) deep main pool is more or less hourglass-shaped, consisting of a larger basin on the western side, connected to a smaller basin on the eastern side. Above the main pool to the backside of the geyser sits a smaller circluar top pool. To the left of the cone a triangular side pool, which is the smallest of the three, is obscured by dense bushes.

Beyond Diamond Geyser the boardwalk passes some high bushes whose low hanging branches arch over Bush Geyser and cast deep shadows on it. For this reason the feature can easily be missed. Bush Geyser sits in front of a low semicircular dry-stone wall. Often the geyser is very active, playing every few minutes up to 50 cm (1.5 feet) height, but at other times the interval is significantly longer or it is dormant. Rarely even eruptions of 1-2 m height were recorded. We observed an interval around 30 minutes, whereby the play lasted only a few seconds. Immediately before the eruption, water surges into the small circular basin to recede just as quickly afterwards.

A few feet farther the bushes discontinue and a view onto the colourful Cascade Terrace opens up. Like all other terraces at Orakei Korako it consists of siliceous sinter and thus differs fundamentally both in the material and in the origin as a fault scarp from travertine terraces such as in Mammoth Hot Springs or Pamukkale. The sign "Hot Springs Algae" in front of the slope is a good yardstick to illustrate the rapid deposition of sinter.

The main feature in this section is Sapphire Geyser. Its small vent halfway up the slope lacks a protruding geyserite cone, and attention is drawn to it only by activity or by the wooden name sign. In the past Sapphire mostly was active when Diamond Geyser was dormant and vice versa. Due to the current long dormancy of Diamond these dependency can no longer be confirmed. Sapphire erupts up to a height of a little more than 2 m (6.5 feet) at intervals in the range of 20 - 30 minutes. The duration of the play is short, but with one or two minutes significantly longer than that of the geysers in its immediate proximity.

On the righthand side (south) of Sapphire Geyser and somewhat higher on the sinter slope two caves are not far from each other. The left, larger one is the outlet of Cascade Geyser, whose vent is hidden deep down inside. Eruptions of Cascade Geyser take place in the depths of the cave, but the angled fountain often splashes out of the cave entrance. Regarding intervals and eruption durations Cascade Geysers behaves very similar to Bush Geyser. During our observation Cascade played every 15 minutes, however, some eruptions hardly did make it to the cave entrance.

In the area around Sapphire Geyser a notable number of smaller geysers has been observed over time, some even got an informal name, but almost all of them were short-living. For example, the geysers with the code S109 and S115 "were located on an intermediate level small terrace just east of Sapphire and informally named Coronation Terrace." (A.D. Cody, Geyser Observations at Orakeikorako, Proceedings 26^th NZ Geothermal Workshop 2004). Further geysers were described by the former owner of the thermal area Tim Boddy, by Edward F. Lloyd, and by T. Scott Bryan.

At the base of Cascade Terrace, just north of Sapphire Geyser, Puia Tuhitarata (Geyser at the Adorned Terrace) shows up. Later it was named Hochstetter Pool in honour of Ferdinand Ritter von Hochstetter, an Austrian geologist and scientific pioneer in the Taupō Volanic Zone in the 19^th century. The pool played as a geyser more than 2 m (6.5 feet) high in 1954 and 1955. Then the acivity was terminated by earthquakes.

North of Hochstetter Pool a notch marks the transition from Cascade Terrace to Rainbow Terrace. The plain in front of Rainbow Fault Scarp is dominated by an unusually dark tinted pool, called Map of Africa. On 28^th May 1996, Terry Spitz, at that time one of the business owners at the Orakei Korako tourist resort, witnessed an eruption of 30 m (98 feet) height from Map of Africa. Nevertheless, geyser activity of this feature seems to be very rare, but it generates stunning mirror images of the surroundings.

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