The highways were originally designated on a two-tier system, National and Provincial, with national highways having a higher standard and funding priorities. The national network consists of Highway 1 running the length of both main islands, Highways 2 to 5 in the North Island, and Highways 6 to 8 in the South Island. State Highways 10 to 58 are in the North Island, SH 60 to SH 99 are in the South Island. State Highways are marked on the side of the road by shield-shaped signs (red for national, blue for provincial) with white numbering, road maps also usually use this convention.
From 2001 information, the busiest stretch of State Highway 1 was the Auckland Harbour Bridge, with over 150,000 cars crossing (either way) each day. The least busy parts of the network (excluding off-ramps and on-ramps) are parts of SH 43 north of Whangamomona which get fewer than 200 cars (counting both directions) in a day. Some of the lesser trafficked highways still contain some unsealed sections.
State Highway 1 starts at Stirling Point, 1 km south of Bluff, and then goes north to Invercargill, and north-east to Gore. It runs due east to Balclutha, then up through Milton to Dunedin. The highway continues along the East Coast past Palmerston, Oamaru and Timaru, moving inland a bit and then north-east through Ashburton to Christchurch. SH 1 continues travelling along the sea up to Kaikoura, looping around to Blenheim and up to Picton at the north of the South Island, terminating at the Inter-island ferry terminal. There have been calls for the ferries themselves to be classified as a component of the highway network, in the belief that this would increase the Governments powers to intervene and keep the ferries running at times of industrial action.
A ferry can be taken to cross Cook Strait, which ends up at the capital city of New Zealand, Wellington.
The northern half of the highway commences at Wellington Airport and runs up the motorway through the Ngauranga gorge to the western coast. Difficult terrain and a large number of satellite towns make this an area of considerable congestion. The Highway passes through Levin and shares the route of SH3 for a 6km dog-leg between the small towns of and Bulls as it crosses the Rangitikei River. Turning Northeast, it follows the river to Taihape, then climbs to the central plateau at Waiouru. The stretch between Waiouru and Turangi is known as the Desert Road, and is frequently closed by snow in winter. There are spectacular views of the three volcanoes Mount Ruapehu, Mount Ngaruahoe and Mount Tongariro.
Turangi is near the southern tip of Lake Taupo and the highway skirts the eastern shore. North of Taupo, the highway turns northwestwards and descends through extensive tracts of plantation forest to Tokoroa and Tirau. Here it joins the Hamilton - Rotorua route and follows the course of the Waikato River through Cambridge to Hamilton. A $NZ 500 million project to convert the entire 160km between Auckland and Cambridge to a four-lane divided carriageway is about 1/3 complete as of late 2003.
From Auckland the highway tends to follow the eastern side of the Northland peninsula, passing through Warkworth, Wellsford, Whangarei and Kaitaia. The highway ends at Waitiki Landing, from which there is a 21 km unsealed road to Cape Reinga.
History of the State Highways
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Since 198?, State Highways have been the responsibility of Transit New Zealand, a state-owned corporation. Since Transit NZ only funds State Highways, city or district councils have sometimes negotiated reallocation of highway routes within their boundaries in order to let Transit part-fund major upgrades to the regional roading network. For example, SH 1 historically ran through the centre of Christchurch, but is now the Christchurch bypass route, while highways 73 and 74 have been extended further into the city to cover major arterial routes.State Highway 1
As mentioned before, SH 1 spans both main islands of New Zealand. There is no road over the Cook Strait, this can be crossed by ferry.List of New Zealand State Highways
National State Highways
North Island Provincial State Highways
South Island Provincial State Highways
(rest to be done)