There are at least three conversions of the first deathmatch level for Quake II, The Edge, for the Quake engine. The level was originally built for the ill fated Quake Arcade Tournament Edition game, and appears there with the filename DM7, but there are also copies named q1edge and a q1edge_v1 released officially by Tim Willits of id Software.
To make matters more confusing, there's a second DM7 for Quake available, entitled Acrophobia / The Count of Death, its not a conversion of The Edge but a lost deathmatch level from the game's development that was retouched and reused in the N64 port of the game and released online for PC gamers shortly after.
Extracts from Tim's comments from the readme of q1edge_v1 follow:
“...I added some teleporters to it in hopes of speeding up gameplay and help prevent camping. [...] For those of you who like to play Quake 1 I hope you enjoy this map.
***This is a fixed version of the map. The map name is now The Edge Conversion.”
For those not familiar with the original, the level consists of a large, almost circular, lemon-shaped room with several ascending staircases around its walls, surrounded by a series of small connecting rooms and corridors filled with military and industrial supplies stored in packing crates, connected to a small outdoor area built into the cliffside with a large pool of water and slime at its base. Diving into the dunk leads through a pipe into a small teleporter room containing a thunderbolt, look upwards here to see designer Tim's initials etched into the second half of the pipe.
There are still a few slight bugs in the final version of this map, it's possible to get caught in the rounded wall in one of the higher areas of the level (near the 3 torches) if you run past holding too closely to it, and there's a leak in the floor as you ascend the stairs from the underground area to the central circular atrium, but only the former presents gameplay problems.
Most of the weapon and item placements in the level are in the same locations as their places in the Quake II version of the level, or represent the closest equivalents between the two. The same goes for textures, although the Quake II texture set was converted for use in Quake this level does not use it, but finds similar items from the standard Quake set to those in the original. Overall the theme here is slightly less high-tech, including themes from the game's third episode, rather than a more direct conversion using the idbase series.
The Edge Conversion works as well in Quake I as it did in Quake II, aside from the slight bugs mentioned earlier in the review, and with the seeming death of the Quake II scene is one of the only ways it can still be played.
There are no secrets in this level, but look upwards near the pipe in the thunderbolt / teleporter room (pictured in thinscreen) to see designer Tim Willits' initials.