diff --git a/src/main/java/com/conveyal/gtfs/model/Entity.java b/src/main/java/com/conveyal/gtfs/model/Entity.java
index 0f092c64f..29657b6e6 100644
--- a/src/main/java/com/conveyal/gtfs/model/Entity.java
+++ b/src/main/java/com/conveyal/gtfs/model/Entity.java
@@ -35,6 +35,7 @@
 import java.sql.SQLException;
 import java.time.LocalDate;
 import java.time.format.DateTimeFormatter;
+import java.time.format.DateTimeParseException;
 import java.util.Enumeration;
 import java.util.Iterator;
 import java.util.Locale;
@@ -213,7 +214,7 @@ protected LocalDate getDateField(String column, boolean required) throws IOExcep
             if (str != null) try {
                 dateTime = LocalDate.parse(str, DateField.GTFS_DATE_FORMATTER);
                 checkRangeInclusive(2000, 2100, dateTime.getYear());
-            } catch (IllegalArgumentException iae) {
+            } catch (IllegalArgumentException | DateTimeParseException e) {
                 feed.errors.add(new DateParseError(tableName, row, column));
             }
             return dateTime;
diff --git a/src/main/java/com/conveyal/gtfs/model/Route.java b/src/main/java/com/conveyal/gtfs/model/Route.java
index 1b9899dd9..c5eb05fbb 100644
--- a/src/main/java/com/conveyal/gtfs/model/Route.java
+++ b/src/main/java/com/conveyal/gtfs/model/Route.java
@@ -106,7 +106,8 @@ public void loadOneRow() throws IOException {
             r.route_branding_url = getUrlField("route_branding_url", false);
             r.feed = feed;
             r.feed_id = feed.feedId;
-            feed.routes.put(r.route_id, r);
+            // Attempting to put a null key or value will cause an NPE in BTreeMap
+            if (r.route_id != null) feed.routes.put(r.route_id, r);
         }
 
     }
diff --git a/src/main/java/com/conveyal/gtfs/model/Stop.java b/src/main/java/com/conveyal/gtfs/model/Stop.java
index d81b677df..25a3ce82a 100644
--- a/src/main/java/com/conveyal/gtfs/model/Stop.java
+++ b/src/main/java/com/conveyal/gtfs/model/Stop.java
@@ -90,8 +90,8 @@ public void loadOneRow() throws IOException {
             s.feed = feed;
             s.feed_id = feed.feedId;
             /* TODO check ref integrity later, this table self-references via parent_station */
-
-            feed.stops.put(s.stop_id, s);
+            // Attempting to put a null key or value will cause an NPE in BTreeMap
+            if (s.stop_id != null) feed.stops.put(s.stop_id, s);
         }
 
     }
diff --git a/src/main/java/com/conveyal/gtfs/model/Trip.java b/src/main/java/com/conveyal/gtfs/model/Trip.java
index 36fb0f896..416854974 100644
--- a/src/main/java/com/conveyal/gtfs/model/Trip.java
+++ b/src/main/java/com/conveyal/gtfs/model/Trip.java
@@ -77,7 +77,8 @@ public void loadOneRow() throws IOException {
             t.wheelchair_accessible = getIntField("wheelchair_accessible", false, 0, 2);
             t.feed = feed;
             t.feed_id = feed.feedId;
-            feed.trips.put(t.trip_id, t);
+            // Attempting to put a null key or value will cause an NPE in BTreeMap
+            if (t.trip_id != null) feed.trips.put(t.trip_id, t);
 
             /*
               Check referential integrity without storing references. Trip cannot directly reference Services or
diff --git a/src/test/java/com/conveyal/gtfs/GTFSMainTest.java b/src/test/java/com/conveyal/gtfs/GTFSMainTest.java
index 4220eaeb5..2c1671922 100644
--- a/src/test/java/com/conveyal/gtfs/GTFSMainTest.java
+++ b/src/test/java/com/conveyal/gtfs/GTFSMainTest.java
@@ -18,6 +18,7 @@
  */
 public class GTFSMainTest {
     private static String simpleGtfsZipFileName;
+    private static String badGtfsZipFileName;
     private final ByteArrayOutputStream outContent = new ByteArrayOutputStream();
 
     // this is used so that it is possible to test code that calls System.exit()
@@ -30,6 +31,7 @@ public static void setUpClass() {
         simpleGtfsZipFileName = null;
         try {
             simpleGtfsZipFileName = TestUtils.zipFolderFiles("fake-agency", true);
+            badGtfsZipFileName = TestUtils.zipFolderFiles("fake-agency-bad-calendar-date", true);
         } catch (IOException e) {
             e.printStackTrace();
         }
@@ -76,4 +78,15 @@ public void canValidateSimpleAgency() throws Exception {
         String[] args = {simpleGtfsZipFileName, "-validate"};
         GTFSMain.main(args);
     }
+
+    /**
+     * Verify that a simple GTFS Zip file can be loaded with the GTFSMain class.
+     *
+     * @throws Exception
+     */
+    @Test
+    public void canValidateFeedWithErrors() throws Exception {
+        String[] args = {badGtfsZipFileName, "-validate"};
+        GTFSMain.main(args);
+    }
 }
diff --git a/src/test/resources/fake-agency-bad-calendar-date/routes.txt b/src/test/resources/fake-agency-bad-calendar-date/routes.txt
index 35ea7aa67..d414aa459 100755
--- a/src/test/resources/fake-agency-bad-calendar-date/routes.txt
+++ b/src/test/resources/fake-agency-bad-calendar-date/routes.txt
@@ -1,2 +1,7 @@
 agency_id,route_id,route_short_name,route_long_name,route_desc,route_type,route_url,route_color,route_text_color,route_branding_url
 1,1,1,Route 1,,3,,7CE6E7,FFFFFF,
+
+
+
+
+