Trivandrum is a beautiful place...beautiful beach, bustling city, full of coconut trees and mangroves in the very southern tip of India.
Favourite spots:
Kovalum Beach. Velly Park.
What's really great:
Kovalum Beach.
Sights:
Kovalum Beach & Velly were nice. There are several shopping plazas/bazaars to get a good deal on touristy & local items.
Restaurants:
Don't eat food from street Vendors, always go to restaurants that offer an A/C room which typically means they offer better food. Fruits are always good.