spider on a cuboid

Henry Dudeney posed a slightly more complex version of this problem ('Spider and Fly') in an English newspaper (Weekly Dispatch) on 14th June 1903

“Inside a rectangular room, measuring 30 feet in length and 12 feet in width and height, a spider is at a point on the middle of one of the end walls, 1 foot from the ceiling, at A, and a fly is on the opposite wall, 1 foot from the floor in the centre at B. What is the shortest distance that the spider must crawl in order to reach the fly, which remains stationary? ”

it later appeared in his collection, 'Canterbury Puzzles' in 1908