Stihl Treetop Walkway
Designed by Glenn Howells Architects with engineers Buro Happold. The STIHL Treetop Walkway starts and finishes on ground level using the topography of the land, rising 13 metres as it follows the valley floor. Opened in the spring of 2016, the elevated walkway takes visitors through the treetop canopy and offers a bird’s eye view of the Westonbirt landscape and tree collection.
“We are very proud to have designed this unique treetop walkway for the historic and internationally renowned arboretum at Westonbirt. The walkway allows all visitors, regardless of age or ability, to experience the site from the treetops for the first time. Focusing on visitor needs and materiality, the walkway is designed to disappear as a sinuous silver ribbon that meanders between trees and canopies. The aim is that this new feature will greatly enhance visitor experience and help to ensure Westonbirt’s popularity for many years to come.” – Architect Glenn Howells said
The sinuous elevated 300-metre route meanders through the arboretum, offering the chance to get up close with trees and the canopy, as well as glorious views across the historic downs landscape.. At four key points, the walkway ‘bulges’ out to form hotspots where visitors can engage with their natural surroundings, and a ‘crows rises up over the walkway, wrapping around a 36-metre tall black pine tree, and offering the chance for people to stop and take in the views.
The walkway has been created by using advanced computational parametric principles and uses materials the complement the surroundings. The distance of any point of legs is the same (10.5 meters) – allowing for a visual continuous flow and foundations are carefully located to avoid impact on existing trees. The steel balustrade is strong and light, minimizing the amount of structure required and reducing the impact on the surroundings, with timber legs chosen as they will age naturally over time.
“People have been enjoying the views of Westonbirt from the ground for generations, so the time has come to offer our visitors a new and exciting way to see the arboretum by getting up close and personal with the canopy. This landmark addition transforms the visitor experience with incredible views which have never been seen before.” – Andrew Smith / Arboretum Director
Today, the walkway is a sinuous structure at one with its surroundings. As it winds through the forest canopy it gives visitors the opportunity to interact with the trees around them, and several platforms dotted along the path further encourage users to pause and reflect on the beauty of the forest beyond.
Glenn Howells Architects:
Westonbirt Arboretum holds one of the finest tree collections in the world, carefully laid out within a beautiful Grade I listed historic landscape. At 284m long the Stihl Treetop Walkway is the longest structure of its kind in the UK, providing stunning new views over the ancient semi-natural woodlands of Silk Wood and the Old Arboretum.
The walkway starts and finishes on ground level using the topography of the land, rising 13 meters above the ground as it follows the valley floor. The route takes the form of a sinuous ‘S’ shape, snaking through the tree canopy with crossing timber legs equally spaced at 10.5 metre intervals holding the walkway in the air. At four points along the route the walkway gently widens, providing spaces for pause, reflection, and interpretation of the surrounding woodland.
The steel balustrade is strong and light, ensuring that the minimum materials were needed to carry people up over the existing pathways, with timber legs chosen as they will age naturally over time. The concept behind the design makes reference to the complexity and elegance behind the fundamental structures of the genetic code of trees.
The world-renowned Westonbirt Arboretum was laid out by three generations of the Holford family from the early 1800s, and has been recognised by Historic England as a Grade I registered Park and Garden of Special Historic Interest. The Westonbirt Heritage Partnership commissioned the walkway to provide visitors with a better understanding of the Arboretum and its landscape, containing the ancient woodlands of Silk Wood and the Downs and to improve visitor accessibility.
“The Grade I listed Westonbirt Arboretum is home to one of the finest tree collections in the world. The Stihl Treetop Walkway provides views over this landscape, in particular the ancient woodlands of Silk Wood and across The Downs. At almost 300m it is the longest structure of its kind in the UK. The walkway bridges across a valley, allowing for ease of access at ground level without any stairs or lifts. While walking along the structure the valley falls away beneath and the walkway rises to over 13.5m above the forest floor. The route snakes above and through the tree canopy supported by scissoring timber legs spaced at 10.5m intervals. At four points along the route it widens from 1.9m to 3.7m, providing spaces for pause and reflection. The walkway is a hybrid timber and steel structure. Larch was selected as the principal material given its durability and attractive colour. Scottish larch was selected for the decking and handrail while the columns are Siberian larch as it offers a tighter grain and higher strength-to-weight ratio.” – Commented / The Wood Awards
Project name: Stihl Treetop Walkway
Location: Westonbirt Arboretum, Westonbirt, Tetbury, GL8 8QS, United Kingdom
Coordinates: 51.606502, -2.216011
Type: Public Facilities, Treetop Walkway
- The final walkway stretches for 294 metres through the treetops
- There are 52 solid larch legs supporting the walkway, and every one is cut to a different length to accommodate the undulating terrain of the forest floor
- Each of the legs is 0.5 metres in diameter and up to 13 metres in length
Project Period: 2009-2016
Status: Built, Completed
Cost: Contract value £1.7 million
Opening Date: April 27, 2016
Visit Kamikatz Public House’s Website: here
Client / Owner / Developer: Forestry Commission
- Glenn Howells Architects – Headquarters, 321 Bradford Street Birmingham, B5 6ET United Kingdom
Main Contractor: Speller Metcalfe
- Structural Engineer: Buro Happold Engineering
- Steel fabricator: SH Structures
- Steel bender: The Angle Ring Company Ltd
- Quantity Surveyor: PMP Consultants
- CDM-C: PMP Consultants
- Interpretation Design: Outside Studios
- Timber column shipwrights: Ventis & Brasker Masten
- Timber decking & handrail: CTS Bridges, Russwood
- Decking & handrail treatment: Koppers Micropro by Norclad
- Rope supply: Bristol Rope & Twine
- Cable-net meshing: Carl Stahl
- Bench joinery/manufacture: Heseltine Design
Text Description: © Courtesy of Glenn Howells Architects, Buro Happold Engineering, SH Structures
Images: © Glenn Howells Architects, Buro Happold Engineering, SH Structures