diff --git a/MarathonData.md b/MarathonData.md
index 008b8f8..eb0fecf 100644
--- a/MarathonData.md
+++ b/MarathonData.md
@@ -381,12 +381,13 @@ main menu, and physics files. Here is a listing of all chunks used within them:
 | `påth` | Not analyzed (å is $8C) (guardpaths)                               |
 | `plac` | Not analyzed (item placement)                                      |
 | `door` | No test data (extra door data)                                     |
-| `PLAT` | No test data (platform static data)                                |
-| `medi` | Media (liquids)                                                    |
+| `plat` | No test data (platform data)                                       |
+| `PLAT` | Not analyzed (saved platform data)                                 |
+| `medi` | Array of Media Data                                                |
 | `ambi` | Array of Ambient Sounds                                            |
 | `bonk` | Array of Random Sounds                                             |
 | `term` | Array of Terminals                                                 |
-| `iidx` | Not analyzed (map indices)                                         |
+| `iidx` | Not analyzed (saved map indices)                                   |
 | `ShPa` | Not analyzed (shapes)                                              |
 | `MMLS` | Not analyzed (MML scripts)                                         |
 | `LUAS` | Not analyzed (Lua scripts)                                         |
@@ -792,6 +793,34 @@ Random Sound is 32 bytes.
 - `Flags` is a Random Sound Flags bit field.
 - `Phase` must be `65535`.
 
+### Media Data ###
+
+Media Data is 32 bytes. "Media" refers to liquids, presumably because of the
+plural of the definition of "medium," a "middle place or degree," as in, it's a
+part of the map in the middle of a wall.
+
+| Name           | Type       | Offset |
+| ----           | ----       | ------ |
+| `Type`         | `u16`      | `0`    |
+| `Flags`        | `u16`      | `2`    |
+| `Control`      | `u16`      | `4`    |
+| `Direction`    | `angle`    | `6`    |
+| `Magnitude`    | `unit`     | `8`    |
+| `Low`          | `unit`     | `10`   |
+| `High`         | `unit`     | `12`   |
+| `Origin`       | `struct`   | `14`   |
+| `Height`       | `unit`     | `18`   |
+| `Minimum`      | `fixed`    | `20`   |
+| `Texture`      | `u16`      | `24`   |
+| `XferMode`     | `u16`      | `26`   |
+
+- `Type` is a Media Type enumeration.
+- `Flags` is a Media Flags bit field.
+- `Control` is the index of a light which is used to control the height of this
+media.
+- `Texture` is an Object ID representing the texture index.
+- `XferMode` is a Transfer Mode enumeration.
+
 ### Static Map Info ###
 
 Static Map Info is 88 bytes.
@@ -1545,6 +1574,15 @@ unobstructed.
 - `Smooth` does a sine transition in the same fashion as `Linear`.
 - `Flicker` flickers between a random smoothed intensity and the final one.
 
+### Media Type ###
+
+| Name           | Value |
+| ----           | ----- |
+| `Water`        | `0`   |
+| `Lava`         | `1`   |
+| `Goo`          | `2`   |
+| `Sewage`       | `3`   |
+
 # FLAGS #######################################################################
 
 ### Endpoint Flags ###
@@ -1749,4 +1787,13 @@ gravity.
 | ----              | ---  |
 | `IgnoreDirection` | `0`  |
 
+### Media Flags ###
+
+| Name              | Bit  |
+| ----              | ---  |
+| `SoundObstruct`   | `0`  |
+
+- `SoundObstruct` means the media makes no sound when under the floor. This is
+most sensible for, for instance, lava which can be drained.
+
 <!-- EOF -->
diff --git a/src/main.rs b/src/main.rs
index 6cd8851..0180bf9 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -57,6 +57,7 @@ fn dump_chunk(opt: &Options, cid: Ident, cnk: &[u8], eid: u16) -> ResultS<()>
          b"OBJS" => make_yaml(opt, &rd_array(cnk, map::read_objs)?)?,
          b"ambi" => make_yaml(opt, &rd_array(cnk, map::read_ambi)?)?,
          b"bonk" => make_yaml(opt, &rd_array(cnk, map::read_bonk)?)?,
+         b"medi" => make_yaml(opt, &rd_array(cnk, map::read_medi)?)?,
          b"term" => make_yaml(opt, &rd_array(cnk, trm::read_term)?)?,
          _ => (),
       }
diff --git a/src/marathon/map.rs b/src/marathon/map.rs
index 8572975..e008bcc 100644
--- a/src/marathon/map.rs
+++ b/src/marathon/map.rs
@@ -255,6 +255,39 @@ pub fn read_bonk(b: &[u8]) -> ResultS<(SoundRand, usize)>
                  yaw_dta, pit_nrm, pit_dta}, 32))
 }
 
+pub fn read_medi(b: &[u8]) -> ResultS<(Media, usize)>
+{
+   read_data! {
+      32, BE in b =>
+      mtype   = u16[0];
+      flags   = u16[2];
+      control = u16[4];
+      dir     = u16[6];
+      mag     = u16[8];
+      hei_lo  = u16[10];
+      hei_hi  = u16[12];
+      orig    = read_point[14..18];
+      hei_nrm = u16[18];
+      min_lt  = u32[20];
+      texture = u16[24];
+      xfer    = u16[26];
+   }
+
+   let mtype   = MediaType::from_repr(mtype)?;
+   let xfer    = TransferMode::from_repr(xfer)?;
+   let texture = ObjID::from_repr(texture);
+   let min_lt  = Fixed::from_bits(min_lt);
+   let hei_nrm = Unit::from_bits(hei_nrm);
+   let hei_hi  = Unit::from_bits(hei_hi);
+   let hei_lo  = Unit::from_bits(hei_lo);
+   let dir     = Angle::from_bits(dir);
+   let mag     = Unit::from_bits(mag);
+   let flr_obs = flags != 0;
+
+   Ok((Media{mtype, flr_obs, control, dir, mag, hei_lo, hei_hi, orig, hei_nrm,
+             min_lt, texture, xfer}, 32))
+}
+
 #[derive(Clone, PartialEq, Serialize)]
 pub struct Point
 {
@@ -380,6 +413,23 @@ pub struct SoundRand
    pub pit_dta: Fixed,
 }
 
+#[derive(Debug, Serialize)]
+pub struct Media
+{
+   pub mtype:   MediaType,
+   pub flr_obs: bool,
+   pub control: u16,
+   pub dir:     Angle,
+   pub mag:     Unit,
+   pub hei_lo:  Unit,
+   pub hei_hi:  Unit,
+   pub orig:    Point,
+   pub hei_nrm: Unit,
+   pub min_lt:  Fixed,
+   pub texture: ObjID,
+   pub xfer:    TransferMode,
+}
+
 #[derive(Debug, PartialEq, Serialize)]
 pub struct Minf
 {
@@ -557,6 +607,17 @@ c_enum! {
    }
 }
 
+c_enum! {
+   #[derive(Debug, Serialize)]
+   pub enum MediaType: u16
+   {
+      0 => Water,
+      1 => Lava,
+      2 => Goo,
+      3 => Sewage,
+   }
+}
+
 impl fmt::Debug for Point
 {
    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result