Breakheart pass is a thrilling suspense novel by Alistair MacLean , which is arguably one of his best works. It was published in 1975 by Ballantine.

Set in the late 1800's gold rush period, the entire story occurs onboard a train, carrying a governer and his niece, accompanied by troops and a US marshal escorting a dangerous outlaw, all heading for Fort Humboldt , a military outpost deep within the Rocky Mountains. The plot involves Red Indians, dangerous desperadoes, train roof fight sequences and gentle romance.

The book is a real pageturner and there are all the classic MacLean elements - sarcastic wit, extreme hyperbole, plot twists, hyper action scenes and completely clean ( good enough for 8 year olds ) storyline and dialogue.
Reading the book, you actually feel like you're on a train, winding through the snowy rockies, across wild, hostile Red Indian territory.

MacLean at his very best - If you read only one MacLean book other than HMS Ulysses, let it be this one.