Hrithik Roshan had a very "filmy" horse. The horse used to know what words like action meant and so when she heard action, she would take off, even if the scene required her to be stationary. Hence the crew would use other words instead of action to avoid the horse taking off. The names of his horses were Chandni and Superman.
In order to acquaint himself with the elephant and strike a comfort level, Hrithik Roshan used to travel to Karjat on days when he was not shooting, just to spend time with the elephant and feed her bananas at lunch. He called him Sweety pie and she would recognize his voice and his cologne.
The film was released in 115 theaters in the USA, making it the biggest American release ever for a Hindi film as of 2008.
Art director Nitin Desai created little cottages for Hrithik Roshan and Aishwarya Rai at his studio because Director Ashutosh Gowariker wanted the actors to stay in Karjat, where they were filming, rather than have them commute from Mumbai every day. They had all the comforts of home in the cottage. Hrithik's wife and son also stayed with him at the cottage.