"Behind the raging horseshoe falls of Niagara there lies a secret like no
other, a century old redbrick tunnel painstakingly laid. There is no
recorded tally of its human cost but in 1906 it would be the biggest
tunnel of its type in the world. The entry cost is a dangerous rappel
through the bowels of a decrepit powerstation into this supervillain
stronghold behind the crashing waterfall."