In the film Superman, Jor-el mentions that there are "28 known galaxies". He makes mention of Krypton not being in the Milky Way. Is there a list of those galaxies?
It has never been made clear, even in apocryphal information from either the scripts of the movies, or the more recent Smallville series (2001-2011) what the names of or the locations of those galaxies were, in relationship to Krypton's home galaxy or the Milky Way.
The DC franchises, as a whole, while retaining the line of text from the Donner script, have never made clear the location of Krypton in relationship to Earth, nor have they ever decided to quantify the list of worlds/galaxies the Kryptonians had relationships with.
If Krypton were within our Milky Way galaxy, there are at least 28 galaxies or more within two million light years of the Milky Way galaxy. This is a list of the closest 28 all within 2.4 million light years of the Milky Way Galaxy. With the faster than light travel Jor-El seemed capable of producing all of these galaxies are within reach of his technology.
I think it (the scripted line) was purely to infer that the Kryptonians were a significantly advanced race and they (laymen movie-watchers) should merely accept the scientific techno-babble.