NH 4 Highway (Port Blair to Diglipur): Route, Length, Challan, Speed Limit, Start and End

Unlike every other highway in this series, NH 4 doesn’t connect to any other national highway — it exists entirely on an island archipelago, cut off from mainland India by the Bay of Bengal. Running 230.7 km from Port Blair to Diglipur, this highway carries a name that reflects its true character: the Great Andaman Trunk Road. For the people of North and Middle Andaman, this isn’t just a highway — it’s the difference between a journey that once took several days by sea and one that now takes 10-12 hours by road.

Here’s the complete, current picture of this genuinely unique highway, including one critical travel restriction you need to know before planning your trip.

NH 4 Quick Facts

Where NH 4 Begins and Ends

NH 4 starts at Port Blair, the capital of the Andaman and Nicobar Islands and home to Veer Savarkar International Airport, the archipelago’s only major air gateway. From there, the highway runs north through South, Middle, and North Andaman, connecting a chain of settlements before terminating at Diglipur, the northernmost significant town on the islands.

Before the 1970s, and continuing into the early 1990s, moving people and goods along this stretch meant relying entirely on sea routes, a journey that could take several days. NH 4’s development transformed this into a 10-12 hour road journey, making it genuinely the lifeline connecting North and Middle Andaman’s communities to the capital and to each other.

The Route Through the Andaman Archipelago

Leaving Port Blair, NH 4 passes through Ferrargunj before reaching the buffer zone of the Jarawa Reserve, a protected area extending from Jirkatang to the Middle Strait. Continuing north, the highway reaches Baratang, an island connected by ferry crossing, before continuing to Kadamtala and Rangat.

From Rangat, the route continues through Billiground, Nimbudera, and Mayabunder before making the final stretch to Diglipur. Along the way, several ferry crossings and water-bound sections are integral to the journey, given the archipelago’s geography — this isn’t a continuous land route in the way mainland highways are, but rather a combination of road and water crossings that together form the complete corridor.

The Jarawa Reserve: The Single Most Important Thing to Know

This is genuinely the most critical piece of information for anyone planning to travel NH 4, and it deserves direct attention rather than a passing mention. The highway passes through the buffer zone of the Jarawa Reserve, home to the Jarawa, one of the indigenous tribal communities of the Andaman Islands. To protect this community and minimize contact between travellers and tribal members, strict laws are in place: only vehicle convoys with armed escorts are permitted to pass through this specific stretch.

This isn’t a casual guideline — it’s a legally enforced protection measure. Independent travel through this section isn’t an option; you’ll need to travel as part of an organized, escorted convoy, and timing your journey around convoy schedules is essential rather than optional. Anyone planning to drive NH 4 needs to build their entire trip timeline around these convoy windows rather than assuming free, independent passage at any hour.

Practical Driving Guidance for This Route

Given the unique circumstances of this highway, several specific practical points matter more here than they would on a typical mainland highway. Starting your trip at night is strongly discouraged and effectively a firm no for most of this route — if a night departure becomes unavoidable, moving slowly and staying genuinely alert matters considerably more than making good time.

Lane discipline deserves particular attention on this route given the mix of local traffic, convoy vehicles, and the narrower sections typical of island infrastructure. Speed itself requires a balanced approach — travelling too fast carries obvious risk, but moving too slowly through certain stretches, particularly timed convoy sections, can create its own complications given the coordinated nature of travel through the reserve zone.

Why NH 4 Matters So Much for Andaman Life

Beyond its role in tourism, NH 4 functions as the essential domestic supply line for the entire Andaman archipelago. Goods arriving in Port Blair from mainland India, whether by sea or air, depend on this highway for onward distribution to North and Middle Andaman communities. This includes movement of essential commodities, access to healthcare facilities, and general connectivity that residents in more remote settlements rely on year-round.

For a region this geographically isolated from mainland India — roughly 1,190 km from Chennai and 1,255 km from Kolkata — a functioning, reliable land route between the capital and the northern islands represents infrastructure that genuinely shapes daily life rather than simply supporting occasional travel.

The Current Upgrade Project

NH 4 is currently undergoing a major upgrade under NHIDCL, involving construction of two significant bridges, with a total project cost of approximately ₹1,511.22 crore. This represents a substantial infrastructure investment for a highway of this length, reflecting the genuine national priority placed on strengthening connectivity across this strategically and ecologically significant archipelago.

Given this active construction status, travellers should expect some sections of NH 4 to reflect ongoing work, and checking current status through NHIDCL or local Andaman administration channels before travel is a sensible step rather than an unnecessary precaution.

Road Conditions Along the Route

Given the archipelago’s forested, island terrain, expect road conditions that differ considerably from mainland highways — narrower sections in places, water crossings requiring ferry transfers, and terrain that shifts through dense forest cover for meaningful stretches of the journey. The ongoing bridge construction work adds another layer of variability, meaning specific sections may currently be under active development rather than fully finished.

Challan and Compliance Notes

Standard Motor Vehicles Act frameworks apply within the Andaman and Nicobar Islands, but the far more consequential compliance matter on this specific highway is respecting the Jarawa Reserve convoy and escort requirements. This isn’t treated as an ordinary traffic regulation — it’s a legally protected measure for indigenous community safety, and non-compliance carries serious consequences well beyond a standard traffic violation.

FAQs

Q1. Can I drive through the Jarawa Reserve section independently if I’m in a hurry?

No — this section is strictly convoy-only, with armed escort required by law. There’s no independent travel option through this stretch regardless of your schedule; plan your entire journey around available convoy timings instead.

Q2. Why does this journey involve ferry crossings if it’s called a highway?

Given the Andaman archipelago’s geography, NH 4 incorporates water crossings, particularly around Baratang, as an integral part of the overall route. This is standard for this specific highway rather than an unusual detour, and travellers should factor ferry timing into their overall journey planning.

Q3. Is it safe to start a journey on NH 4 at night?

It’s strongly discouraged for most of the route. If a night departure is genuinely unavoidable, drive slowly and stay especially alert, but planning for daytime travel is the far more sensible default given the road conditions and convoy timing requirements involved.

Q4. How has NH 4 changed daily life for people in North and Middle Andaman?

Significantly — journeys that once took several days by sea before the 1970s now take roughly 10-12 hours by road. This has transformed access to essential goods, healthcare, and general connectivity for communities that were previously far more isolated from Port Blair and the rest of the archipelago.