A list of popular road trip routes to Kerala from Bangalore
NH544 towards Kerala near Kerala-Tamilnadu border
Central Kerala
Bangalore to Ernakulam (Option 1) Bangalore → Hosur → Krishnagiri → Salem → Bhavani → Coimbatore → Palakkad → Thrissur → Ernakulam
Bangalore to Ernakulam (Option 2) Bangalore → Hosur → Krishnagiri → Salem → Dindigul → Theni → Munnar → Ernakulam
Bangalore to Kottayam (Option 1) Bangalore → Hosur → Krishnagiri → Salem → Bhavani → Coimbatore → Palakkad → Thrissur → Ernakulam → Kottayam
Bangalore to Kottayam (Option 1) Bangalore → Hosur → Krishnagiri → Salem → Dindigul → Theni → Kumily → Kottayam
South Kerala
Bangalore to Kollam Bangalore → Hosur → Krishnagiri → Salem → Dindigul → Madurai → Tenkasi → Kollam
Bangalore to Thiruvananthapuram Bangalore → Hosur → Krishnagiri → Salem → Dindigul → Madurai → tirunelveli → Nagercoil → Thiruvananthapuram
There are many alternate route others than the major one show. Customise route according to tour itinerary and final destination.
There's also a central north-south highway in Kerala (NH66), almost parallel to NH44 in Tamilnadu. For reaching southern parts of Kerala, plan maximum itinerary on the on the NH44, before taking diversions into Kerala. The highways in Kerala are generally bussy, curvy and with many junctions, compared to the fast moving traffic on the Tamilnadu highways.
Kerala is connected with Bangalore through NH544 and NH44.
Take the diversion on the NH44 , depending on where you are heading to in Kerala.