apart from, you know, being 20,000 leagues under the sea, which is 1.1112e+8 metres accoridng to google. and submarines so deep in the ocean that they are actually deep in the space on the other side... or maybe it's just ISS?
"The title refers to the distance traveled while under the sea and not to a depth, as 20,000 leagues is over six times the diameter, and nearly twice the circumference of the Earth.[2] The greatest depth mentioned in the book is four leagues. The book uses metric leagues, which are four kilometres each"
(https://en.wikipedia.org/wiki/Twenty_Thousand_Leagues_Under_...)