Check the Pathways Official Hint Book for a nice overview of the heights and depths in the game before we start.

The Entrance

When you start the game the Player Window tells you that:

You are 0.0m above ground.

Since the first level is called Ground Floor this makes perfect sense. Of course, you might be confused by this since the game box, manual cover and start-up screen show a soldier (presumably the player) approaching a pyramid with an entrance at the top. For more dicussion on this and a possible explanation see The Pyramid section.

Meters or Feet?

Interesting to note that while PID is a US developed game, the heights and depths are given in meters (m) rather than feet (ft). Feet are referred to in the Story Introduction in a sentence which oddly mixes both the metric system of units and the United States customary units.

The object itself was buried thousands of feet below ground, its nearly two kilometer length remarkably intact.

Climbing

The first part of the game, aptly named 'The Pyramid', is above ground and comprises seven levels. Each of these levels is reached by climbing a crudely constructed wooden ladder. Nice of someone to have left these. In the Pathways Demo (Version A1) there was a CLIMB button which became active when you approached a ladder. Clicking this button allowed you ascend (or descend) to another level. This feature (or restriction) was removed in the full game. Simply walking into a ladder allowed you to ascend (or descend) to the next level.

On They May Be Slow... you will find two secret areas with teleporters. These allow you to move between levels instanteously. Very handy, particularly later on. ;)

Apart from teleporters there are Crystal Ladders and Vines to help you navigate between levels.

Moving between level

An important feature in the game is the ability to freely move between levels. Indeed it is part of the game play. You will find areas that you can't access without first obtaining an item from another level. Remembering to go back is of course the trick. However this freedom to move between levels isn't absolute and is restricted in one unfortunate way.

As discussed on the Barnies?!!! section if you try returning to the last level after killing the Demon you cannot pass back through "Warning: Earthquake Zone" as a door is now locked.

Why would you want to return to the last level again?

Well there are a number of reasons:

1. You failed to pick up the Alien Gemstone. (Easily overlooked amongst all the bodies).
2. You forgot to arm the bomb. (Has been known to happen).
3. You didn't get the code change off Steven. (Like I have to remember ALL this stuff).
4. You failed to pick up the Lead Box on Warning: Earthquake Zone. (Afterall you had other things to worry about).
5. The Lead Box was one of the items you just happened to drop while mapping the teleporter maze. (Jason Jones told you to do this!).

Any of these mistakes could have been correctable if you could only go back down.

Pyramid scale

Back in 2012, I posted the following pic on the Story forum. I wrote:

This gives you some idea of the scale of our mission. ;)
While we don't know the actual height of the pyramid it
has to be over 15.6m and probably under 50m.

Also interesting to note is the size of the Dreaming God.

Hopper posted the following pic of the PID levels against a scale of height and depth. He wrote:

All that climbing on ladders feels kinda pointless by the end, doesn't it?

Hopper provided a better comparison of the earlier levels.

The Lower Elevations

As discussed on The Cuban Conundrum section the elevation of a number of the lower levels is jumbled up. This raised the question as to "How did Javier and Carlos get down so far?"

Below are the five levels in the Hole, their elevations and the remains of former level names.

Don't Get Poisoned!re Tread	(-1042.4m)
Please Excuse Our DustAll!	(-102.5m)
But Wait!- That's Not All!	(-327.2m)
Where Only Fools Dare Tread	(-326.7m)
Ok, Who Else Wants Some?	(-3276.8m)

It would suggest that "Don't Get Poisoned!" with an elevation of -1042.4m should be the second last level and that the levels "Where Only Fools Dare Tread" and "Don't Get Poisoned!" were interchanged at some point. This may have been done to make the opening of the Glass Vial (thus releasing the Demon) and its eventual appearance much closer.

Also interesting to note that two levels have almost the same depth. Since they are connected by teleporters this can happen.

Jeoku writes about the depth of the final level "Ok, Who Else Wants Some?":

The depth of Ok, Who Else wants some? is at elevation 3276.8. 32768 is 2 to the 15th power
and is the maximum absolute value that the "integer" value can hold in a program.