near
Kadavoor {{Maplink|frame=yes|plain=yes|frame-width=300|frame-height=450|zoom=7|frame-lat=10.493971 |frame-long=76.066196|frame-align=right Kerala has eight National Highways which run for about 1811.52 km. Kerala has narrower National Highways compared to other parts of India. Kerala is the only state, other than Goa, which has requested for narrower highways in the state.
NHAI upgrades highways to a minimum 4-lane, 60-meter-wide, grade-separated highway or a better standard across India. But in Kerala, National Highways are being upgraded to 45-meter-wide highways. Previous Kerala State Government had requested the NHAI to reduce the width of National highways in the state to 30-meters, although neighbouring Karnataka and Tamil Nadu are upgrading their National Highways as 60-meters or more wider highways, with futuristic provision for 6/8-lane highway. The reason cited by the State Government was the difficulty and disinterest in Land Acquisition, which is the responsibility of the State Government. NHAI had stopped working on many of the highway widening/upgrade projects as there are opposition from the local population for highway widening. Among Kerala's
districts,
Ernakulam has the maximum length of National Highway, which accounts for 172.76 km.
Wayanad has the minimum length of National Highway in Kerala. Government has taken steps to develop the
NH 66 (
Kasargod to
Thiruvananthapuram) into six lane. But, proposed six lane highways with 45 m Right of Way in Kerala will not have the wide medians to help the trucks and large vehicles to take the U-Turn without blocking the high speed traffic, which is a common feature in other parts of India. Wider median also helps to block the opposite side vehicle headlamp with plants.
Six-laning of National Highways in Kerala Kerala's first four lane National Highway is the
NH 66 stretch between
Cherthala and
Aroor and first six lane National Highway is the
NH 544 stretch between
Thrissur and
Vadakkencherry. Kerala's first and biggest six lane tunnel highway is also on this stretch at
Kuthiran. It is the part of
Kochi -
Thrissur-
Palakkad-
Walayar stretch of
NH 544. -
Vadakkencherry at
Ponnani,
Malappuram, the largest Regulator-cum-bridge in the state, is built over the river
Bharathappuzha Bharatmala Pariyojana has identified 418 km of national highway and State highway stretches in Kerala. Keeping in view a futuristic approach, it has been decided that the land for any 4/6-lane highway road will be acquired with a right of way (RoW) of 60 m irrespective of the width of the carriageway. Kerala has not been allocated Greenfield 8-lane
access-controlled expressways like other south Indian states as part of
Bharatmala Pariyojana, as many brownfield projects of
NHDP projects have still not started. The
Palakkad—
Thrissur—
Kochi stretch of
NH 544 is a part of
North-South and East-West Corridor of the Indian highway system. Due to the previous land acquisition crisis, NHAI had also stopped the feasibility study of the project under
NHDP–Phase-III scheme in the stretch of NH 66 earlier, but has begun again after the strict demand of present Chief Minister. There was a proposal for construction of standalone ring road/bypasses around Thiruvananthapuram City under NHDP Phase VII. ==State highways==