diff --git a/nextflow_schema.json b/nextflow_schema.json
index dc5a3c3f..02984622 100644
--- a/nextflow_schema.json
+++ b/nextflow_schema.json
@@ -183,6 +183,13 @@
                     "help_text": "Saving generated references means that you can use them for future pipeline runs, reducing processing times.",
                     "fa_icon": "fas fa-save"
                 },
+                "igenomes_base": {
+                    "type": "string",
+                    "format": "directory-path",
+                    "description": "Directory / URL base for iGenomes references.",
+                    "default": "s3://ngi-igenomes/igenomes/",
+                    "fa_icon": "fas fa-cloud-download-alt"
+                },
                 "igenomes_ignore": {
                     "type": "boolean",
                     "description": "Do not load the iGenomes reference config.",
@@ -499,11 +506,5 @@
         {
             "$ref": "#/$defs/generic_options"
         }
-    ],
-    "properties": {
-        "igenomes_base": {
-            "type": "string",
-            "default": "s3://ngi-igenomes/igenomes/"
-        }
-    }
+    ]
 }