Organ Pipes National Park Loop Walk

On Thursday, 30 November 2017, one other hiker joined me for a morning walk around Organ Pipes National Park on Melbourne’s north-western fringe.

This was another exploratory Green Trails event. I had cycled down into the park as a child and wanted to return to see whether its main geological attractions could be connected into a short loop.

The original estimate was approximately 2.5km. Our completed walk measured 3.05km, with 115 metres of elevation gain, and took 52 minutes.

Hike details

Date: Thursday, 30 November 2017
Location: Organ Pipes National Park, Victoria
Hike type: Loop
Recorded distance: 3.05km
Completion time: 52 minutes
Elevation gain: 115m
Number of hikers: Two, including the hike leader
Difficulty: Grade 3 due to the steep descent and return climb
Main features: The Organ Pipes, Rosette Rock, Tessellated Pavement, Jacksons Creek and valley views

Returning to a childhood destination

Organ Pipes National Park was a familiar place from my childhood, when I used to cycle down into the valley. Returning years later as the leader of a Green Trails hike gave me an opportunity to explore it from a different perspective.

The park is relatively small, but the steep valley and distinctive geological formations give it far more variety than its size might suggest. Our plan was to connect its main attractions into a loop if the available tracks allowed it. If not, we would simply follow the designated paths and enjoy a short morning walk before the day became too warm.

With only two of us attending, it was a relaxed opportunity to investigate the tracks and photograph the landscape.

Looking across Organ Pipes National Park from the top of the valley.

Descending into the Jacksons Creek valley

The walk began above the Jacksons Creek valley. From the higher ground, the route descended steeply towards the creek and the main geological attractions.

Although much of the principal access path is broad and formed, its gradient should not be underestimated. The steep return climb accounts for much of the 115 metres of elevation recorded during this otherwise short walk.

Descending from the upper section of the park into the valley.

Broad walking path passing through the trees.

The surrounding Keilor Plains appear comparatively flat, making the deep valley carved by Jacksons Creek particularly striking. Views from the upper slopes show how sharply the land drops away from the surrounding plain.

How the Organ Pipes were formed

The park protects several unusual rock formations created by volcanic activity and subsequently exposed by erosion.

Approximately one million years ago, lava from volcanic hills near present-day Sunbury flowed across the Keilor Plains and filled depressions in the existing landscape. As the lava cooled and contracted, cracks developed and divided the solidifying basalt into columns.

Over a very long period, Jacksons Creek cut down through the basalt plain and exposed the columns. Their long, regular appearance resembles the pipes of a large musical organ, giving both the formation and the national park their names.

The Organ Pipes rising beside Jacksons Creek.

These formations are protected within the national park and should only be observed and photographed. Rocks, plants and other natural material must remain where they are found.

Following Jacksons Creek

The lower walking tracks follow Jacksons Creek through the valley, passing rocky slopes, woodland and exposed sections of basalt.

Rock formations beside the creekside walking trail.

Basalt rocks exposed along the valley slope.

Sunlight reflecting from the creek added another element to the otherwise dry and rocky landscape.

Sunlight glistening across Jacksons Creek.

The rocks seen throughout the valley record different stages in its geological history. In addition to the volcanic basalt, the park contains much older sandstone and mudstone. These sedimentary rocks were laid down beneath an ancient sea approximately 400 million years ago, long before the later lava flows covered the area.

Rosette Rock and the Tessellated Pavement

Rosette Rock is another example of the way cooling lava can produce striking geometric formations. Instead of standing vertically like the Organ Pipes, its basalt columns radiate outwards like the spokes of a wheel.

The radial basalt columns of Rosette Rock.

Farther along the creek, the Tessellated Pavement consists of the exposed tops of basalt columns worn down by the action of Jacksons Creek. Viewed from above, the resulting pattern resembles a constructed pavement of closely fitted tiles.

Together, the Organ Pipes, Rosette Rock and Tessellated Pavement demonstrate how the direction and speed of cooling, followed by a long period of erosion, can expose very different patterns within the same volcanic landscape.

Plants and signs of restoration

The park’s vegetation has undergone a substantial recovery. When Organ Pipes National Park was established in 1972, much of the former farmland was heavily affected by weeds. Decades of weed removal and revegetation have helped native trees, shrubs and groundcover return to the valley.

Among the plants photographed during our walk were the soft, feathery seed heads of a climbing plant from the Clematis genus, commonly known as old man’s beard.

We also passed an arrangement of fallen branches that someone had leaned against a tree in the shape of a small shelter.

Fallen branches arranged against a tree. If used, avoid implying that it is an official structure.

Remnants of the park’s farming history

On the opposite side of the creek, we could see part of an old homestead. The park contains remnants of its European farming history, including the remains of a stone house dating from the nineteenth century.

Remains of an old homestead viewed across Jacksons Creek.

These ruins are part of the park’s protected cultural landscape. They provide a reminder that the area was used for farming and grazing before being reserved as a national park and progressively restored.

Organ Pipes National Park is located on Wurundjeri Woi Wurrung Country. Jacksons Creek formed part of the boundary between the Marin-Balluk and Wurundjeri-Willam clan estates, and archaeological surveys have recorded Aboriginal campsites and artefacts within the park.

Completing our short loop

Our exploratory walk developed into a 3.05km loop and took 52 minutes to complete. Although it was a short outing, the steep descent and climb produced a total elevation gain of 115 metres.

The walk provided much more than its distance might suggest. Within approximately an hour, we encountered volcanic formations, a deeply eroded creek valley, restored native vegetation, historic ruins and elevated views across the park.

A small daypack containing water, sun protection and a basic first-aid kit is sufficient for most visitors. Even on short outings, carrying water is important because the exposed upper slopes can become hot. Green Trails has a broader selection of day-hiking equipment for short walks and longer adventures.

This Green Trails group walk was organised and managed through Meetup. The original details can be viewed on the Organ Pipes National Park Loop Meetup event.

Anyone planning a present-day visit should consult the official Organ Pipes National Park information for current access conditions, facilities and visitor advice.