Some of the oldest trig stations in NSW are in Sydney’s north, which was extensively surveyed in in the early 1880s. The Trigonometrical Survey of New South Wales commenced in 1867 with the selection of the first baseline at Lake George, with most of the trigs in Sydney’s north constructed in the early 1880s. The history of these trig stations was extensively documented by Tony Dawson in Guide to the Historic Trig Stations of Sydney’s North (2007).
Early Surveys and Land Grants
While the rugged terrrain of Sydney’s north meant it avoided development in the first decade of Sydney’s colonisation, by the early 1800s the first portions of land were granted. In 1807 James Meehan surveyed a parcel of land for William Gore and Isaac Nicholls, and in 1814 a 400-acre allotment was given to Daniel Mathew at what is now Roseville. Between 1814 and 1821 (before retiring in 1822), Meehan mapped the coast and lagoons between Barrenjoey and Manly Beach, with 17 land grants being made in this area.
Arriving in Sydney in 1827 as the deputy Surveyor General, Major Thomas Livingstone Mitchell undertook a more systematic approach, adopting trigonometrical principles to divided the colony into counties and parishes. (A year later with the death in May 1828 of John Oxley, Mitchell became the Surveyor General, remaining in charge of the Survey Department until he died in 1855.) Supported by a team of surveyors, Mitchell divided the colony into nineteen counties and mapped Sydney’s north as far as Church Point. Despite these efforts, even by the 1870s the parish maps were still fairly inccurate, with warnings such as “The position of the Railway Line from Homebush to Waratah as shown hereon is only approximately correct due to the inaccuracy of the map”…
A new approach is needed
In January 1855 William Thomas Denison arrived in Sydney as the new Governor-General, and quickly concluded that the Surveyor-General’s Department needed a drastic overhaul. He found that the lack of any permanent reference maps meant that the cadastral mapping system was unreliable: in many cases boundaries were incorrect and portions of land encroached each other, sometimes by a significant amount. Despite Mitchell’s “trigonometric approach”, Denison’s Commission of Enquiry found that the previous surveys “could not have any claim to the character of of a ‘trigonometric survey’ in the correct and ordinarily received acceptation of the term“. By the early 1860s, stations used for triangulation were established in the Albury area, and in 1869 Lake George was selected as the most suitable location to establish a Base Line that would extend across the colony.
A formal Trigonometric Survey is established in the north
In December 1880, Pittwater Trig on Tumbledown Dick Hill (the highest point on the Lane Cove Range) was built by Thomas Charles Swannell, a piling overseer. Over the next few years, Swannel and his team built over 80 trig stations across Sydney’s north – most of them substantial stone cairns up to two metres in height. Most of the trig sites were high points along the main ranges, which were often challenging to reach. Before the trig station could be built, the hill or high point had to be cleared of trees.
At the same time as Swannel was building the trigs, connecting these into a network (which would form the basis of accurate maps) was the job of the Trigonometric Branch. First class stations were used for large-scale triangulations – forming triangles with sides up to 60km in length – while the more numerous second-class and third-class stations were used for lcoal surveys. During the 1880s much of this work was done by Frank Burdett, who made extensive surveys around the Hawkesbury River and Cowan Creek, and played an important role in the survey of the Parish of Manly. His legacy is witnessed by the many arrows cut into the rock as survey marks, although he also used the newly established trig stations as reference points.
Summary of original Sydney North Trig Stations
The trig stations below were listed in the 1895 Register for the Trigonometric Survey of NSW and the 1891 Register for the City of Sydney.
| Name | Number | Built | Location | Height | Condition |
|---|---|---|---|---|---|
| Addison | TS594 | 1882 | 33°41’11.4″S 151°15’30.7″E | 200m | Partly destroyed |
| Allison | TS620 | 1882 | 33°40’17.0″S 151°08’33.7″E | 195m | Destroyed |
| Arden | TS638 | 1882 | 33°38’02.9″S 151°15’03.4″E | 206m | Damaged |
| Arthur | TS649 | 1882 | 33°38’53.5″S 151°11’47.5″E | 192m | Good |
| Bangalley / South Head | TS4135 | 1882 | 33°37’24.5″S 151°20’28.3″E | 116m | Damaged (new trig 1976) |
| Bairne | TS681 | 1882 | 33°36’50.8″S 151°17’10.0″E | 183m | Good |
| Bantry | TS728 | 1881 | 33°46’41.9″S 151°14’21.9″E | 137m | Good (restricted access) |
| Barbara | TS734 | 1883 | 33°40’35.8″S 151°07’14.9″E‘ | 183m | Destroyed |
| Bare | TS739 | 1881 | 33°43’03.7″S 151°13’08.3″E | 195m | Destroyed |
| Barrenjoey | TS7220 | 1882 | S33° 34.758′ E151° 19.716′ | 104m | Good |
| Barrenjoey Lighthouse | TS10091 | 1882 | 33°34’48.7″S 151°19’47.5″E | 102m | Good (passive trig) |
| Bates | TS784 | 1882 | 33°46’34.0″S 151°13’00.0″E | 108m | Destroyed |
| Beaumont | TS801 | 1882 | 33°38’39.3″S 151°08’09.2″E | 220m | Destroyed |
| Belrose | TS6324 | NEW | 33°43’03.4″S 151°13’08.7″E | 207m | Good (restricted access) |
| Bobbin | TS1013 | 1883 | 33°40’12.7″S 151°09’42.1″E | 180m | Partly destroyed |
| Boundary | TS1100 | 1881 | 33°42’27.2″S 151°12’12.1″E | 189m | Good |
| Bradleys | TS1131 | 33°51’08.7″S 151°14’46.5″E | 30m | Good | |
| Brown | TS1184 | 1881 | 33°45’30.0″S 151°06’47.6″E | 90m | Destroyed |
| Bushranger | TS1321 | 1882 | 33°39’48.7″S 151°19’04.4″E | 103m | Good |
| Carrol | TS1421 | 1882 | 33°44’04.8″S 151°11’15.6″E | 166m | Good |
| Castlecrag | TS10293 | 33°47’59.4″S 151°13’16.1″E | 93m | Good (trig plug only) | |
| Carvossa | TS1426 | c.1881 | 33°48’20.9″S 151°10’35.6″E | 100m | Destroyed |
| Cliff | TS1490 | 1882 | 33°34’52.3″S 151°14’03.9″E | 184m | Damaged |
| Cole | TS1531 | 1882 | 33°35’06.3″S 151°12’23.3″E | 201m | Damaged |
| Cook | TS1582 | 1883 | 33°41’58.2″S 151°07’35.2″E | 201m | Good |
| Cowan | TS1672 | 1881 | 33°39’10.8″S 151°10’28.2″E | 197m | Damaged |
| Dee Why | TS1796 | 1881 | 33°45’52.9″S 151°18’06.1″E | 49m | Good |
| Djarra | TS1839 | 1883 | 33°35’28.4″S 151°09’21.3″E | 210m | Good (restricted access) |
| Dobroyd Point | TS1840 | 33°48’28.3″S 151°16’08.7″E | 91m | Destroyed | |
| Duffy | TS1890 | 1882 | 33°40’37.9″S 151°12’53.9″E | 210m | Good |
| Edith | TS1935 | 1883 | 33°45’12.4″S 151°10’34.3″E | 124m | Destroyed |
| Edwards | TS1940 | 1882 | 33°35’07.6″S 151°13’02.8″E | 184m | Partly destroyed |
| Eliza | TS1948 | 1883 | 33°45’35.5″S 151°10’11.2″E | 111m | Destroyed |
| Ellis | TS1955 | 1882 | 33°38’52.9″S 151°13’44.9″E | 195m | Mostly destroyed |
| Ethel | TS1985 | 1883 | 33°35’53.5″S 151°10’24.0″E | 205m | Damaged |
| Euro | TS2005 | 1882 | 33°35’59.8″S 151°17’17.4″E | 169m | Good |
| Eva | TS2012 | 1882 | 33°41’06.7″S 151°11’02.8″E | 188m | Mostly destroyed |
| Evelyn | TS2015 | 1882 | 33°36’14.5″S 151°08’54.3″E | 212m | Destroyed |
| French | TS2109 | 1882 | 33°44’15.5″S 151°13’14.1″E | 175m | Good (trig plug only) |
| Gordon | TS2276 | 1881 | 33°46’25.1″S 151°08’41.2″E | 70m | Not Found |
| Gore | TS5607 | c.1880 | 33°49’16.1″S 151°11’08.7″E | 101m | Destroyed |
| Gundah | TS2358 | 1882 | 33°37’43.0″S 151°07’31.1″E | 222m | Mostly destroyed |
| Gunson | TS2380 | 1882 | 33°41’48.8″S 151°16’03.7″E | 175m | Good (trig plug only) |
| Hamley | TS2399 | 1882 | 33°38’13.6″S 151°08’40.3″E | 218m | Good |
| Harnett | TS2415 | 33°50’10.0″S 151°14’48.1″E | 100m | Destroyed | |
| Harvey | TS2427 | 1882 | 33°40’10.3″S 151°14’03.7″E | 199m | Mostly destroyed |
| Hecla | TS2461 | 1882 | 33°36’23.3″S 151°08’05.5″E | 225m | Destroyed |
| Hungry | TS2531 | 1882 | 33°39’18.7″S 151°13’39.4″E | 197m | Partly destroyed |
| Ida | TS2548 | 1883 | 33°45’00.7″S 151°09’55.4″E | 120m | Destroyed |
| Jacomb | TS2581 | 1883 | 33°41’00.8″S 151°09’41.3″E | 166m | Mostly Destroyed |
| Johnson | TS2632 | 1882 | 33°38’57.6″S 151°16’57.3″E | 120m | Destroyed |
| Jones | TS2636 | 1881 | 33°46’04.3″S 151°14’04.9″E | 131m | Good |
| L8 | TS2780 | 33°49’20.0″S 151°13’06.4″E | 70m | Destroyed | |
| Lix | TS2868 | 1881 | 33°40’47.0″S 151°16’26.4″E | 179m | Good |
| Lloyd | TS1871 | 1883 | 33°32’48.1″S 151°11’27.4″E | 210m | Good |
| Long | TS2882 | 1882 | 33°38’13.7″S 151°10’37.2″E | 206m | Damaged |
| Long Reef | TS2888 | 1881 | 33°44’29.4″S 151°18’53.4″E | 36m | Good (new trig 1972) |
| Lucy | TS2904 | 1882 | 33°39’50.0″S 151°07’21.1″E | 190m | Good (trig plug) |
| Mcintosh | TS3025 | 1882 | 33°39’55.4″S 151°16’43.0″E | 165m | Damaged |
| Maggie | N/A | 1882 | 33°41’48.4″S 151°16’09.4″E | 205m | Destroyed |
| Manly | TS2962 | 1881 | 33°45’14.4″S 151°15’50.9″E | 155m | Good |
| McCarr | TS3015 | 1882 | 33°39’07.4″S 151°15’40.7″E | 191m | Damaged |
| McComb | TS6234 | 1881 | 33°47’01.5″S 151°15’29.2″E | 81m | Good |
| McCowen | TS3018 | 1882 | 33°40’09.8″S 151°15’50.4″E | 184m | Good |
| Middle Cove | TS10010 | 33°47’41.7″S 151°13’15.5″E | 88m | Good (trig plug) | |
| Middle Harbour | TS5550 | 1881 | 33°45’47.4″S 151°12’35.6″E | 128m | Damaged |
| Millicent | TS3112 | 1883 | 33°35’05.8″S 151°10’45.7″E | 230m | Good |
| Mole | TS5083 | 1883 | 33°42’33.8″S 151°11’21.8″E | 176m | Good (trig plug) |
| Narrabeen | TS3329 | 1882 | 33°42’35.0″S 151°15’51.4″E | 135m | Partly destroyed |
| North | TS3553 | 1883 | 33°43’19.5″S 151°10’50.6″E | 165m | Good (trig plug) |
| Northbridge | TS2575 | 1882 | 33°48’26.0″S 151°13’35.9″E | 88m | Good (trig plug) |
| Obelisk | TS3597 | 1809 | 33°49’08.4″S 151°17’37.4″E | 72m | Good |
| Peate | TS3691 | 1881 | 33°40’18.0″S 151°06’29.1″E | 212m | Good (trig plug) |
| Pittwater | TS6957 | 1880 | 33°41’08.5″S 151°14’03.1″E | 218m | Partly destroyed |
| Poppy | TS3791 | 1882 | 33°37’08.2″S 151°08’49.8″E | 220m | Destroyed |
| Quarantine | TS3818 | 33°48’54.1″S 151°17’55.5″E | 105m | Partly destroyed | |
| Powell | TS3792 | 1883 | 33°45’50.5″S 151°09’24.5″E | 120m | Destroyed |
| Ramsay | TS3841 | 1881 | 33°43’44.2″S 151°17’32.0″E | 100m | Destroyed |
| Roach | TS3914 | 1882 | 33°39’00.5″S 151°10’57.9″E | 207m | Mostly destroyed |
| Robertsons | TS3920 | 33°50’54.6″S 151°13’58.1″E | 10m | Destroyed | |
| Ryland | TS3991 | 1882 | 33°41’36.7″S 151°11’41.9″E | 187m | Partly destroyed |
| Sandy | TS4023 | 1882 | 33°40’53.8″S 151°11’58.9″E | 198m | Good |
| Smart | TS4112 | 1882 | 33°44’18.0″S 151°09’09.2″E | 160m | Destroyed |
| Soutar | TS4132 | 1882 | 33°44’31.8″S 151°10’26.7″E | 130m | Destroyed |
| Taber | TS5929 | 1882 | 33°37’51.3″S 151°12’28.2″E | 204m | Mostly destroyed |
| Terry | TS4323 | 1881 | 33°41’46.3″S 151°13’08.9″E | 207m | Unknown (private land) |
| Topham | TS5653 | 1882 | 33°36’30.3″S 151°15’47.7″E | 227m | Damaged |
| Turimetta | TS4478 | 1882 | 33°41’43.0″S 151°18’42.8″E | 59m | Good |
| Vize | TS4551 | 1883 | 33°34’19.6″S 151°11’27.9″E | 225m | Mostly destroyed |
| Wallaroo | TS4576 | 1882 | 33°36’30.3″S 151°15’47.7″E | 194m | Partly destroyed |
| Waller | TS4580 | 1882 | 33°44’00.7″S 151°10’33.0″E | 150m | Destroyed |
| Want | TS4609 | 1882 | 33°36’17.4″S 151°11’55.7″E | 198m | Partly destroyed |
| Waratah | TS4625 | 1882 | 32°54’13.9″S 151°43’03.3″E | 196m | Partly destroyed |
| Wheeler | TS4735 | 1881 | 33°43’54.7″S 151°15’25.1″E | 145m | Destroyed |
| White | TS4745 | 1882 | 33°39’41.2″S 151°10’41.4″E | 202m | Partly destroyed |
| Wilkins | TS4763 | 1882 | 33°39’23.6″S 151°12’07.9″E | 195m | Partly destroyed |
| Willunga | TS4779 | 1882 | 33°37’05.4″S 151°15’30.8″E | 232m | Partly destroyed |
| Wright | TS4861 | 1880 | 33°44’29.3″S 151°08’20.8″E | 160m | Unknown |
| Yatala | TS4923 | 1883 | 33°36’46.5″S 151°09’35.6″E | 220m | Good |