diff --git a/src/doomdef.h b/src/doomdef.h
index 4fd50e92..a44fe477 100644
--- a/src/doomdef.h
+++ b/src/doomdef.h
@@ -427,9 +427,6 @@ extern const char *compdate, *comptime, *comprevision, *compbranch;
 ///	\note	obsoleted by cv_maxportals
 //#define PORTAL_LIMIT 8
 
-///	Fun experimental slope stuff!
-//#define SLOPENESS
-
 /// Kalaron/Eternity Engine slope code (SRB2CB ported)
 #define ESLOPE
 
diff --git a/src/hardware/hw_glob.h b/src/hardware/hw_glob.h
index 83dff02f..94eef1d3 100644
--- a/src/hardware/hw_glob.h
+++ b/src/hardware/hw_glob.h
@@ -36,9 +36,7 @@ typedef struct
 {
 	float x;
 	float y;
-//#ifdef SLOPENESS
 	float z;
-//#endif
 } polyvertex_t;
 
 #ifdef _MSC_VER
diff --git a/src/hardware/hw_main.c b/src/hardware/hw_main.c
index 409900b9..58e4e87f 100644
--- a/src/hardware/hw_main.c
+++ b/src/hardware/hw_main.c
@@ -539,6 +539,8 @@ static void HWR_RenderPlane(sector_t *sector, extrasubsector_t *xsub, fixed_t fi
 	static FOutVector *planeVerts = NULL;
 	static UINT16 numAllocedPlaneVerts = 0;
 
+	(void)sector;
+
 	// no convex poly were generated for this subsector
 	if (!xsub->planepoly)
 		return;
@@ -678,25 +680,6 @@ static void HWR_RenderPlane(sector_t *sector, extrasubsector_t *xsub, fixed_t fi
 		v3d->x = pv->x;
 		v3d->y = height;
 		v3d->z = pv->y;
-#ifdef SLOPENESS
-		if (sector && sector->special == 65535)
-		{
-			size_t q;
-			for (q = 0; q < sector->linecount; q++)
-			{
-				if (v3d->x == sector->lines[q]->v1->x>>FRACBITS)
-				{
-					if (v3d->z == sector->lines[q]->v1->y>>FRACBITS)
-					{
-						v3d->y += sector->lines[q]->v1->z>>FRACBITS;
-						break;
-					}
-				}
-			}
-		}
-#else
-		(void)sector;
-#endif
 	}
 
 	// only useful for flat coloured triangles
diff --git a/src/p_spec.c b/src/p_spec.c
index 285da0e7..277fe19e 100644
--- a/src/p_spec.c
+++ b/src/p_spec.c
@@ -6028,31 +6028,6 @@ void P_SpawnSpecials(INT32 fromnetsave)
 				P_AddRaiseThinker(lines[i].frontsector, &lines[i]);
 				break;
 
-#ifdef SLOPENESS
-			case 999:
-				sec = sides[*lines[i].sidenum].sector-sectors;
-				for (s = -1; (s = P_FindSectorFromLineTag(lines + i, s)) >= 0 ;)
-				{
-					size_t counting;
-
-					sectors[s].floorangle = ANGLE_45;
-					for (counting = 0; counting < sectors[s].linecount/2; counting++)
-					{
-						sectors[s].lines[counting]->v1->z = sectors[sec].floorheight;
-						CONS_Debug(DBG_GAMELOGIC, "Set it to %d\n", sectors[s].lines[counting]->v1->z>>FRACBITS);
-					}
-
-					for (counting = sectors[s].linecount/2; counting < sectors[s].linecount; counting++)
-					{
-						sectors[s].lines[counting]->v1->z = sectors[sec].ceilingheight;
-						CONS_Debug(DBG_GAMELOGIC, "Set it to %d\n", sectors[s].lines[counting]->v1->z>>FRACBITS);
-					}
-					sectors[s].special = 65535;
-					CONS_Debug(DBG_GAMELOGIC, "Found & Set slope!\n");
-				}
-				break;
-#endif
-
 			case 200: // Double light effect
 				P_AddFakeFloorsByLine(i, FF_EXISTS|FF_CUTSPRITES|FF_DOUBLESHADOW, secthinkers);
 				break;
diff --git a/src/r_defs.h b/src/r_defs.h
index f18410fe..2915b925 100644
--- a/src/r_defs.h
+++ b/src/r_defs.h
@@ -369,14 +369,6 @@ typedef struct sector_s
 	double lineoutLength;
 #endif // ----- end special tricks -----
 
-	// ZDoom C++ to Legacy C conversion (for slopes)
-	// store floor and ceiling planes instead of heights
-	//secplane_t floorplane, ceilingplane;
-#ifdef SLOPENESS
-	//fixed_t floortexz, ceilingtexz; // [RH] used for wall texture mapping
-	angle_t floorangle;
-#endif
-
 	// This points to the master's floorheight, so it can be changed in realtime!
 	fixed_t *gravity; // per-sector gravity
 	boolean verticalflip; // If gravity < 0, then allow flipped physics