diff --git a/src/person.cpp b/src/person.cpp
--- a/src/person.cpp
+++ b/src/person.cpp
@@ -251,7 +251,7 @@ static const WalkInformation _walk_sw_sw
 };
 /** Walk from SW edge to NW edge. */
 static const WalkInformation _walk_sw_nw[] = {
-{ANIM_WALK_NE, WLM_LOW_X},  {ANIM_WALK_NW, WLM_NW_EDGE}, {ANIM_INVALID, WLM_INVALID}
+	{ANIM_WALK_NE, WLM_LOW_X},  {ANIM_WALK_NW, WLM_NW_EDGE}, {ANIM_INVALID, WLM_INVALID}
 };
 
 /** Walk from NW edge to NE edge. */
@@ -327,7 +327,7 @@ static const WalkInformation _center_sw_
 };
 /** Walk from SW edge to centre NW edge. */
 static const WalkInformation _center_sw_nw[] = {
-{ANIM_WALK_NE, WLM_MID_X},  {ANIM_WALK_NW, WLM_NW_CENTER}, {ANIM_INVALID, WLM_INVALID}
+	{ANIM_WALK_NE, WLM_MID_X},  {ANIM_WALK_NW, WLM_NW_CENTER}, {ANIM_INVALID, WLM_INVALID}
 };
 
 /** Walk from NW edge to centre NE edge. */
@@ -356,6 +356,54 @@ static const WalkInformation *_center_pa
 };
 
 /**
+ * Encode a walk into a number for serialization.
+ * @param wi Walk to encode.
+ * @return The encoded walk.
+ */
+static uint16 EncodeWalk(const WalkInformation *wi)
+{
+	for (int i = 0; i < 4; i++) {
+		for (int j = 0; j < 4; j++) {
+			int k = 0;
+			const WalkInformation *wij = _walk_path_tile[i][j];
+			while (wij->anim_type != ANIM_INVALID) {
+				if (wi == wij) return (0 << 12) | (i << 8) | (j << 4) | k;
+				k++;
+				wij++;
+			}
+		}
+	}
+	for (int i = 0; i < 4; i++) {
+		for (int j = 0; j < 4; j++) {
+			int k = 0;
+			const WalkInformation *wij = _center_path_tile[i][j];
+			while (wij->anim_type != ANIM_INVALID) {
+				if (wi == wij) return (1 << 12) | (i << 8) | (j << 4) | k;
+				k++;
+				wij++;
+			}
+		}
+	}
+}
+
+/**
+ * Decode a walk number back to a walk.
+ * @param number Value to decode.
+ * @return The walk encoded by the number.
+ */
+static const WalkInformation *DecodeWalk(uint16 number)
+{
+	int k = number & 0xF;
+	int j = (number >> 4) & 0xF;
+	int i = (number >> 8) & 0xF;
+	int c = (number >> 12) & 0xF;
+	if (c == 0) return &_walk_path_tile[i][j][k];
+	if (c == 1) return &_center_path_tile[i][j][k];
+
+	NOT_REACHED();
+}