The eighth largest US state Colorado is also its highest –the average height is almost 7,000ft and there are 50 peaks over 14,000ft. From the 1850s its population rocketed with the discovery of vast deposits of gold and silver, aided by the construction of a network of 3ft gauge railroads, some of which survive today.

The talk starts in the state capital Denver before an extensive tour of some of the best known tourist sights, amidst the grandeur of the autumnal mountain scenery. Of the several railroads featured that at Pikes Peak is the most spectacular, the highest in America and the highest cog railway in the World.