Took the public transport everywhere. Can be tiring cos the roads in Kerala are curvy everywhere. Cost effective. Also took trains from Guruvayur to Chalakudy, Chalakudy to Alleppey and from Kottayam to Kozhikode.
Visit the Guruvayur Krishna Temple. Better to go for a very early morning darshan as the crowd is less and you get more time to spend inside the temple.Visit the Elephant Sanctuary. Its just 3 kms away from Guruvayur. It opens at 8AM. Ticket cost is Rs. 10. Spend 1-2 hours here.
One of the best waterfalls in South India. I took a bus from Challakudy Private Bus Stand. 1 hour journey. Ticket counter is ahead of the waterfalls entry point. So you may get down from Bus one stop ahead.Little bit of walking to reach the waterfalls. You can also go down the hill to get the full view of waterfalls. Bathing is permitted but be careful. Best time to visit is post monsoon when the falls is fully loaded.
Backwaters are amazing!!! I took a Govt jetty from Alleppey Govt Boat Jetty. It costs just Rs. 25 for a 2 hour ride till Kottayam. Its basically used by the locals. There are various routes available. Alleppey - Kottayam is the most scenic of all. There is a boat every 1-2 hours. CHeck the timetable the previous day. Stayed @ Snehadhara Homestay. Get awesome food...Dosa, Pomfret fry, Channa Curry etc. Massage is available here. But found it to be just ok.Don't forget to visit the beach in the evening.
Visit the Periyar Tiger Reserve. Get the bookings done for Trekking/Hiking/Row Boat. Its a must do to experience the beauty of the Jungle early in the morning. You are accompanied by forest ranger and guards. You don't get to see the tiger. But you can see some Elephants and Bison.Avoid the boating. Its waste of time and money.Visit the spice Plantations. Famous for Cardamom, Pepper etc.