This is the coverdisk of PC Zone's March 1997 Issue, It contains 500 Levels for Quake, 500 levels for Duke Nukem 3D, and Demos of games including Heroes Of Might & Magic 2, F1 Manager and other games and other goodies, This file is not by me and I do not own it either, This file came from archive.org
To install Quake maps, drag them to the Quake folder and place the BSP files in Map folder, Duke 3D maps need to be placed in the gameroot maps folder of either the 20th anniversary world tour or megaton edition or place them in a add-on folder for Eduke32.
Simply select demos to start them, and install the game to wherever you want on the PC/Laptop you have.