diff --git a/pystac/validation/stac_validator.py b/pystac/validation/stac_validator.py
index 35d6d826f..1117e9fd3 100644
--- a/pystac/validation/stac_validator.py
+++ b/pystac/validation/stac_validator.py
@@ -210,6 +210,8 @@ def _validate_from_uri(
             msg += f"against schema at {schema_uri}"
 
             best = jsonschema.exceptions.best_match(errors)
+            if best:
+                msg += "\n" + str(best)
             raise STACValidationError(msg, source=errors) from best
 
     def validate_core(
diff --git a/tests/test_item.py b/tests/test_item.py
index c3274d003..83e4ad529 100644
--- a/tests/test_item.py
+++ b/tests/test_item.py
@@ -13,7 +13,7 @@
 
 import pystac
 import pystac.serialization.common_properties
-from pystac import Asset, Catalog, Collection, Item, Link
+from pystac import Asset, Catalog, Collection, Item, Link, STACValidationError
 from pystac.utils import (
     datetime_to_str,
     get_opt,
@@ -630,3 +630,10 @@ def test_non_hierarchical_relative_link() -> None:
     assert a.target_in_hierarchy(b)
     assert root.target_in_hierarchy(next(b.get_items()))
     assert root.target_in_hierarchy(root)
+
+
+def test_invalid_error_message(item: Item) -> None:
+    item.extra_fields["collection"] = "can't have a collection"
+    with pytest.raises(STACValidationError) as error:
+        item.validate()
+    assert "can't have a collection" in str(error.value)