diff --git a/modules/core/src/main/java/org/locationtech/jts/operation/relateng/DimensionLocation.java b/modules/core/src/main/java/org/locationtech/jts/operation/relateng/DimensionLocation.java
index 6aa32b286d..bcdc421ac2 100644
--- a/modules/core/src/main/java/org/locationtech/jts/operation/relateng/DimensionLocation.java
+++ b/modules/core/src/main/java/org/locationtech/jts/operation/relateng/DimensionLocation.java
@@ -14,6 +14,13 @@
 import org.locationtech.jts.geom.Dimension;
 import org.locationtech.jts.geom.Location;
 
+/**
+ * Codes which combine a geometry dimension and a location
+ * on the geometry.
+ * 
+ * @author mdavis
+ *
+ */
 class DimensionLocation {
 
   public static final int EXTERIOR = Location.EXTERIOR;
diff --git a/modules/core/src/main/java/org/locationtech/jts/operation/relateng/NodeSection.java b/modules/core/src/main/java/org/locationtech/jts/operation/relateng/NodeSection.java
index dd59d7bf50..f707df0109 100644
--- a/modules/core/src/main/java/org/locationtech/jts/operation/relateng/NodeSection.java
+++ b/modules/core/src/main/java/org/locationtech/jts/operation/relateng/NodeSection.java
@@ -95,6 +95,12 @@ public int ringId() {
     return ringId;
   }
   
+  /**
+   * Gets the polygon this section is part of.
+   * Will be null if section is not on a polygon boundary.
+   * 
+   * @return the associated polygon, or null
+   */
   public Geometry getPolygonal() {
     return poly;
   }
diff --git a/modules/core/src/main/java/org/locationtech/jts/operation/relateng/RelateGeometry.java b/modules/core/src/main/java/org/locationtech/jts/operation/relateng/RelateGeometry.java
index 57ad0ef5ae..e84713ad63 100644
--- a/modules/core/src/main/java/org/locationtech/jts/operation/relateng/RelateGeometry.java
+++ b/modules/core/src/main/java/org/locationtech/jts/operation/relateng/RelateGeometry.java
@@ -178,6 +178,12 @@ public boolean hasDimension(int dim) {
     return false;
   }
   
+  /**
+   * Gets the actual non-empty dimension of the geometry.
+   * Zero-length LineStrings are treated as Points.
+   * 
+   * @return the real (non-empty) dimension
+   */
   public int getDimensionReal() {
     if (isGeomEmpty) return Dimension.FALSE;
     if (getDimension() == 1 && isLineZeroLen)
@@ -208,6 +214,10 @@ public int locateLineEnd(Coordinate p) {
 
   /**
    * Locates a vertex of a polygon.
+   * A vertex of a Polygon or MultiPolygon is on
+   * the {@link Location#BOUNDARY}.
+   * But a vertex of an overlapped polygon in a GeometryCollection
+   * may be in the {@link Location#INTERIOR}.
    * 
    * @param pt the polygon vertex
    * @return the location of the vertex
diff --git a/modules/core/src/main/java/org/locationtech/jts/operation/relateng/RelatePointLocator.java b/modules/core/src/main/java/org/locationtech/jts/operation/relateng/RelatePointLocator.java
index 35ae78f2e9..f4942e78c3 100644
--- a/modules/core/src/main/java/org/locationtech/jts/operation/relateng/RelatePointLocator.java
+++ b/modules/core/src/main/java/org/locationtech/jts/operation/relateng/RelatePointLocator.java
@@ -152,13 +152,21 @@ public int locateLineEnd(Coordinate p) {
    * (i.e. a point or on an edge).
    * 
    * @param p the node point to locate
-   * @param polygonal 
+   * @param parentPolygonal the polygon the point is a node of
    * @return the location of the node point
    */
   public int locateNode(Coordinate p, Geometry parentPolygonal) {
     return DimensionLocation.location(locateNodeWithDim(p, parentPolygonal));
   }
   
+  /**
+   * Locates a point which is known to be a node of the geometry,
+   * as a {@link DimensionLocation}.
+   * 
+   * @param p the point to locate
+   * @param parentPolygonal the polygon the point is a node of
+   * @return the dimension and location of the point
+   */
   public int locateNodeWithDim(Coordinate p, Geometry parentPolygonal) {
     return locateWithDim(p, true, parentPolygonal);
   }