Option 1:
via Dindigul, Tirunelveli, Nagercoil:
Bangalore - Krishnagiri - Dharmapuri - Salem - Karur - Dindigul - Madurai outskirts - Thirumangala - Virudhunagar - Sattur - Kovilpatti - Tirunelveli bypass (KTC Nagar) - Kavalkinaru junction (NH44 and NH944), turn right and continue on NH944 - Nagerkovil (Nagercoil) - Marthandam - Trivandrum.
Road conditions and distances:
* Bangalore to Tirunelveli Bypass (KTC Nagar) is excellent 4 or 6 lane road with median divider = 585 kms/ 9 hrs.
* Tirunelveli (KTC Nagar) (NH44) to Kavalkinaru Junction (crossing of NH44 and NH944) is excellent 4 or 6 lane road with median divider = 63 kms/ 1 hr.
* Kavalkinaru Junction (crossing of NH44 and NH944) to Nagercoil (crossing of NH944 and NH66) decent 2 lane road = 22 kms.
* Nagercoil to Trivandrum International Airport crossing via bypass/ NH66 is decent but 2 lane road with heavy traffic = 67 kms.
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Option 2:
via Salem, Coimbatore bypass, Palakkad, Thrissur, Ernakulam, Alleppey.
Bangalore - Krishnagiri - Dharmapuri - Salem - Coimbatore bypass - Palakkad - Thrissur - Aluva - Ernakulam - Alleppey - Kallambalam - Trivandrum International Airport crossing.
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