diff --git a/plugins/catalog-backend/migrations/20241003170511_alter_target_in_locations.js b/plugins/catalog-backend/migrations/20241003170511_alter_target_in_locations.js
index d909186a73..855e1a7f8d 100644
--- a/plugins/catalog-backend/migrations/20241003170511_alter_target_in_locations.js
+++ b/plugins/catalog-backend/migrations/20241003170511_alter_target_in_locations.js
@@ -31,6 +31,16 @@ exports.up = async function up(knex) {
  * @returns { Promise<void> }
  */
 exports.down = async function down(knex) {
+  const oversizedEntries = await knex('locations').where(
+    knex.raw('LENGTH(target) > 255'),
+  );
+
+  if (oversizedEntries.length > 0) {
+    throw new Error(
+      `Migration aborted: Found ${oversizedEntries.length} entries with 'target' exceeding 255 characters. Manual intervention required.`,
+    );
+  }
+
   await knex.schema.alterTable('locations', table => {
     table.string('target').alter();
   });
diff --git a/plugins/catalog-backend/src/tests/migrations.test.ts b/plugins/catalog-backend/src/tests/migrations.test.ts
index 370241dda1..873746ac2b 100644
--- a/plugins/catalog-backend/src/tests/migrations.test.ts
+++ b/plugins/catalog-backend/src/tests/migrations.test.ts
@@ -345,7 +345,7 @@ describe('migrations', () => {
         .into('locations');
 
       // Verify that both the simple and long URLs exist after the migration
-      await expect(knex('locations')).resolves.toEqual(
+      await expect(knex('locations').where({ type: 'url' })).resolves.toEqual(
         expect.arrayContaining([
           {
             id: '1f99f7f6-1d87-4e8c-994a-8a2ba1d542f6',
@@ -361,6 +361,18 @@ describe('migrations', () => {
         ]),
       );
 
+      await expect(migrateDownOnce(knex)).rejects.toThrow(
+        `Migration aborted: Found 1 entries with 'target' exceeding 255 characters. Manual intervention required.`,
+      );
+
+      // Now remove the long URL
+      await knex('locations')
+        .where({
+          id: '1f99f6f7-1d87-4e8c-994a-2a8ba1d542f6',
+        })
+        .del();
+
+      // Retry the migration down after removing the long URL
       await migrateDownOnce(knex);
 
       // Verify that the column type has reverted to varchar
@@ -369,20 +381,14 @@ describe('migrations', () => {
         /^(varchar|character varying)$/,
       );
 
-      // Verify that both the simple and long URLs exist after the rollback
-      await expect(knex('locations')).resolves.toEqual(
+      // Verify that the short URL still exists in the table
+      await expect(knex('locations').where({ type: 'url' })).resolves.toEqual(
         expect.arrayContaining([
           {
             id: '1f99f7f6-1d87-4e8c-994a-8a2ba1d542f6',
             target: 'https://example.com',
             type: 'url',
           },
-          {
-            id: '1f99f6f7-1d87-4e8c-994a-2a8ba1d542f6',
-            target:
-              'https://example.com/foo-bar-test-group/very-long-group-name-that-exceeds-255-characters-just-to-test-the-limits-of-url-length-in-the-catalog-info-yaml-file-and-see-how-the-backstage-system-handles-it-making/test-this-alright-1/-/blob/main/catalog-info.yaml',
-            type: 'url',
-          },
         ]),
       );