N1 (Bangladesh)

The N1 or Dhaka–Chittagong Highway is the main transportation artery of Bangladesh, connecting the capital city of Dhaka and the southern port city of Chittagong. Approximately 465 km in length, the highway starts at Jatrabari in Dhaka and ends at Teknaf in Cox's Bazar. The highway is known along certain stretches as the Chittagong–Cox's Bazar Highway and the Cox's Bazar–Teknaf Highway.

Currently four lanes with an eight-lane expansion underway, the N1 is the busiest road in the country and a top development priority.

Background
When constructed, the highway was limited to two lanes of traffic for most of its length. Traffic jams or tailbacks of 25 km have been reported. In 2009, it was estimated that daily usage of the highway was 20,000–25,000 motorised vehicles, up 40% of which were trucks.

The highway forms a critical component of the proposed Asian Highway Network route AH41 and the Central-South-East Asian economic corridor, including initiatives such as BCIM.

Four lanes
In January 2010, construction work to expand the Dhaka–Chittagong stretch from two to four lanes commenced. The project was expected to decrease travel time from Dhaka to Chittagong to 4.5 or 5 hours.

As of March 2013, only 23.5 per cent of work has been completed, and it was unlikely to meet its December 2013 deadline. Construction included 221 culverts, 22 bridges and three flyovers. Reza Construction Ltd. and Sino Hydro have set temporary camps for this purpose respectively near Daudkandi and Chandina in Comilla District.

After inauguration being postponed several times, the project, implemented by the Roads and Highways Department (RHD), was finally completed and opened on 2 July 2016, three years behind schedule and a full decade after the plan was approved.

The total cost for the expansion of the stretch was, up from the initial estimate of in 2006.

Eight lanes
An upgrade of the Dhaka–Chittagong section to eight lanes to start construction by late 2024 or early 2025 is on the cards. Portions of the 229 km road will be converted into six lanes, while others will be expanded to eight lanes. The total cost of the project is estimated at. The Asian Development Bank (ADB) will provide financing for this project—which is going to be implemented in three phases—according to the RHD.

Bypass lanes
The RHD is planning to alleviate traffic congestion on the Chittagong–Cox's Bazar route by constructing bypass lanes and flyovers at five crucial points. This initiative is prompted by the upcoming opening of the Matarbari Deep Sea Port in 2026, which is anticipated to increase traffic on the current two-lane highway. The project includes the construction of four-lane bypasses at Patiya (5.4 km), Dohazari (3.3 km), Lohagara (5.1 km), and Chakaria (6.8 km), along with a six-lane flyover at Keranihat (3.5 km).

Four lanes
The RHD is also upgrading the Chittagong–Cox's Bazar highway to four lanes, at an initial estimated cost of. This project aims to expand 110 km of the 169 km highway into four lanes, as sections of the highway have already been upgraded earlier.

In Dhaka District
From Jatrabari to Signboard 6 km in Dhaka District.

In Narayanganj District
This highway runs on three Upazilas of Narayangaj district. Upazilas are Narayanganj Sadar Upazila, Bandar Upazila and Sonargaon Upazila. From Signboard to Meghna Bridge, total length of N1 highway runs on this district is 19 km.

In Munshiganj District
The highway exceeded only one Upazila of Munshiganj district and that is Gazaria Upazila. From Meghna Bridge to Meghna-Gomti bridge, total length of highway runs on this district is 11 km.

In Comilla District
N1 exceeds five Upazilas of Comilla district, Daudkandi Upazila, Chandina Upazila, Burichang Upazila, Comilla Sadar Upazila and Chauddagram Upazila. Length of N1 in Comilla district is 97 km.

In Feni District
N1 exceeded two Upazila of Feni district, Feni Sadar Upazila and Chhagalnaiya Upazila. Length of N1 in Feni district is 31 km.

In Chittagong District
N1 exceeds seven upazilas on Chittagong district including Chittagong city. Upazilas are Mirsharai Upazila, Sitakunda Upazila, Boalkhali Upazila, Patiya Upazila, Chandanaish Upazila, Satkania Upazila and Lohagara Upazila. Length of N1 in Chittagong District is 148.06 km.

In Cox's Bazar District
N1 exceeds four upazilas of Cox's bazar district. Upazilas are Chakaria Upazila, Ramu Upazila, Ukhia Upazila and Teknaf Upazila. Length of N1 in Cox's Bazar District is 148.87 km.