I knew king cobras were big but to see a man holding one, it really drives home its size! They're the largest *venomous* snakes in the world. Their venom is a powerful neurotoxin causing respiratory and cardiac arrest. Yet they try to avoid people, snakes (including other types of cobra) being their only diet. Probably due to habitat loss, they're now listed as vulnerable.
Rattlesnakes have a forked tongue that they flick up and down. The tongue picks microscopic airborne particles and gases from the air. When the tongue slips back into its mouth, it touches a sensitive spot on the roof of the mouth called the vomeronasal organ, or Jacobson's organ. This organ picks up the particles collected by the tongue and sends messages to the snake's brain identifying the scent as food, enemy, mate or other object or substance.
Essentially if you are horrified of snakes you should consider passing up on traveling to India. The Indian Cobra is the next member of India’s ‘Big Four’ and one of the most deadly. They make up the majority of all snakebites toward humans in the country of India. The Indian Cobra has great stature in the country thanks to their placement in Indian mythos and culture and they are often seen being used by ‘snake charmers’. This close proximity to Indian residents is why so many active bites.