diff --git a/3DGeoVolumes/collections/NewYork/NewYork.json b/3DGeoVolumes/collections/NewYork/NewYork.json
deleted file mode 100644
index 4dd0f8d81eaf899fc0c7c3080231c3a475724387..0000000000000000000000000000000000000000
--- a/3DGeoVolumes/collections/NewYork/NewYork.json
+++ /dev/null
@@ -1,75 +0,0 @@
-{
-    "links": [
-      {
-        "rel": "self",
-        "href": "host_url/collections/NewYork",
-        "type": "application/json",
-        "title": "All geospatial data available in the New York area"
-      }
-    ],
-    "collections": [
-      {
-        "id": "NewYork",
-        "title": "NewYork Data Source",
-        "description": "All Supported 3D Containers for the city of NewYork",
-        "collectiontype": "3d-container",
-        "extent": {
-          "spatial": {
-            "bbox": [
-              [
-                -74.01900887327089,
-                40.700475291581974,
-                -11.892070104139751,
-                -73.9068954348699,
-                40.880256294183646,
-                547.7591871983744
-              ]
-            ],
-            "crs": "http://www.opengis.net/def/crs/OGC/0/CRS84h"
-          }
-        },
-        "links": [
-          {
-            "rel": "collections",
-            "href": "host_url/collections/",
-            "type": "application/json"
-          },
-          {
-            "title": "NewYork - 3D Buildings Manhattan",
-            "rel": "self",
-            "href": "host_url/collections/NewYork/",
-            "type": "application/json"
-          },
-          {
-            "title": "NewYork - 3D Buildings Manhattan: 3D Tiles",
-            "rel": "items",
-            "href": "host_url/collections/NewYork/3dtiles",
-            "type": "application/json+3dtiles"
-          },
-          {
-            "title": "NewYork - 3D Buildings Manhattan: i3s",
-            "rel": "items",
-            "href": "https://tiles.arcgis.com/tiles/P3ePLMYs2RVChkJx/arcgis/rest/services/Buildings_NewYork_17/SceneServer/layers/0/",
-            "type": "application/json+i3s"
-          }
-        ],
-        "children": [
-          
-        ],
-        "content": [
-          {
-            "title": "NewYork - 3D Buildings Manhattan: 3D Tiles",
-            "rel": "original",
-            "href": "host_url/collections/NewYork/3dtiles/",
-            "type": "application/json+3dtiles"
-          },
-          {
-            "title": "NewYork - 3D Buildings Manhattan: i3s",
-            "rel": "original",
-            "href": "https://tiles.arcgis.com/tiles/P3ePLMYs2RVChkJx/arcgis/rest/services/Buildings_NewYork_17/SceneServer/layers/0/",
-            "type": "application/json+i3s"
-          }
-        ]
-      }
-    ]
-  }
\ No newline at end of file
diff --git a/3DGeoVolumes/collections/Stuttgart/Stuttgart.json b/3DGeoVolumes/collections/Stuttgart/Stuttgart.json
deleted file mode 100644
index 81715ecb51b6f087ce46db8055aac3f1f70b1c0f..0000000000000000000000000000000000000000
--- a/3DGeoVolumes/collections/Stuttgart/Stuttgart.json
+++ /dev/null
@@ -1,146 +0,0 @@
-{
-    "links": [
-      {
-        "rel": "self",
-        "href": "host_url/collections/Stuttgart",
-        "type": "application/json",
-        "title": "Stuttgart 3D models"
-      }
-    ],
-    "collections": [
-      {
-        "id": "Stuttgart",
-        "title": "Stuttgart 3D Models Demo",
-        "description": "All Supported 3D Containers for the city of Stuttgart LoD 1 from OSM with Textures",
-        "collectiontype": "3d-container",
-        "extent": {
-          "spatial": {
-            "bbox": [
-              [9.161434,48.771841,-10,9.183426,48.786318,550]
-            ],
-            "crs": "http://www.opengis.net/def/crs/OGC/0/CRS84h"
-          }
-        },
-        "links": [
-          {
-            "rel": "collections",
-            "href": "host_url/collections/",
-            "type": "application/json"
-          },
-          {
-            "title": "Stuttgart 3D Building Model (LoD 1) - Collections",
-            "rel": "self",
-            "href": "host_url/collections/Stuttgart_LoD1_OSM_Textures/",
-            "type": "application/json"
-          },
-          {
-            "title": "Stuttgart 3D Building Model (LoD 1) : 3D Tiles",
-            "rel": "items",
-            "href": "https://steinbeis-3dps.eu/3DGeoVolumes/collections/Stuttgart/Stuttgart_3DBuildings_LoD1/3dtiles/",
-            "type": "application/json+3dtiles"
-          }
-        ],
-        "children": [
-          {
-            "id": "HFTBuilding2_3DModel",
-            "title": "HFT Building 2 - 3D Model",
-            "description": "3D Building Model of the HFT Stuttgart created by SketchUp and converted with CityEngine and FME.",
-            "collectiontype": "3d-container",
-            "extent": {
-              "spatial": {
-                "bbox": [
-                  [
-                    9.1729205436,
-                    48.7794377214,
-                    -10,
-                    9.1738475153,
-                    48.7802408522,
-                    550
-                  ]
-                ],
-                "crs": "http://www.opengis.net/def/crs/OGC/0/CRS84h"
-              }
-            },
-            "links": [
-              {
-                "rel": "collections",
-                "href": "https://steinbeis-3dps.eu/3DGeoVolumes/collections/",
-                "type": "application/json"
-              },
-              {
-                "title": "Stuttgart Collections",
-                "rel": "self",
-                "href": "https://steinbeis-3dps.eu/3DGeoVolumes/collections/Stuttgart",
-                "type": "application/json"
-              },
-              {
-                "title": "HFT Building 2 - 3D Model: i3s",
-                "rel": "items",
-                "href": "https://steinbeis-3dps.eu/3DGeoVolumes/collections/Stuttgart/HFTBuilding2_3DModel/i3s",
-                "type": "application/json+i3s"
-              },
-              {
-                "title": "HFT Building 2 - 3D Model: 3D Tiles",
-                "rel": "items",
-                "href": "https://steinbeis-3dps.eu/3DGeoVolumes/collections/Stuttgart/HFTBuilding2_3DModel/3dtiles",
-                "type": "application/json+3dtiles"
-              },
-              {
-                "title": "HFT Building 2 - 3D Model: USDZ",
-                "rel": "items",
-                "href": "https://steinbeis-3dps.eu/3DGeoVolumes/collections/Stuttgart/HFTBuilding2_3DModel/usdz",
-                "type": "application/usdz"
-              },
-              {
-                "title": "HFT Building 2 - 3D Model: gltf",
-                "rel": "items",
-                "href": "https://steinbeis-3dps.eu/3DGeoVolumes/collections/Stuttgart/HFTBuilding2_3DModel/gltf",
-                "type": "application/gltf"
-              }
-            ],
-            "children": [],
-            "content": [
-              {
-                "title": "HFT Building 2 - 3D Model: i3s",
-                "rel": "items",
-                "href": "https://steinbeis-3dps.eu/3DGeoVolumes/collections/Stuttgart/HFTBuilding2_3DModel/i3s",
-                "type": "application/json+i3s"
-              },
-              {
-                "title": "HFT Building 2 - 3D Model: 3D Tiles",
-                "rel": "original",
-                "href": "https://steinbeis-3dps.eu/3DGeoVolumes/collections/Stuttgart/HFTBuilding2_3DModel/3dtiles",
-                "type": "application/json+3dtiles"
-              },
-              {
-                "title": "HFT Building 2 - 3D Model: USDZ",
-                "rel": "original",
-                "href": "https://steinbeis-3dps.eu/3DGeoVolumes/collections/Stuttgart/HFTBuilding2_3DModel/usdz",
-                "type": "application/usdz"
-              },
-              {
-                "title": "HFT Building 2 - 3D Model: gltf",
-                "rel": "original",
-                "href": "https://steinbeis-3dps.eu/3DGeoVolumes/collections/Stuttgart/HFTBuilding2_3DModel/gltf",
-                "type": "application/gltf"
-              }
-            ]
-          }
-        ],
-        "content": [
-          {
-            "title": "Stuttgart 3D Building Model (LoD 1) - Collections",
-            "rel": "original",
-            "href": "host_url/collections/Stuttgart_LoD1_OSM_Textures/",
-            "type": "application/json"
-          },
-          {
-            "title": "Stuttgart 3D Building Model (LoD 1) : 3D Tiles",
-            "rel": "original",
-            "href": "https://steinbeis-3dps.eu/3DGeoVolumes/collections/Stuttgart/Stuttgart_3DBuildings_LoD1/3dtiles/",
-            "type": "application/json+3dtiles"
-          }
-        ]
-      }
-    ]
-  }
\ No newline at end of file
diff --git a/3DGeoVolumes/collections/Stuttgart/Stuttgart_LOD2_Stadtmitte/Stuttgart_LOD2_Stadtmitte.json b/3DGeoVolumes/collections/Stuttgart/Stuttgart_LOD2_Stadtmitte/Stuttgart_LOD2_Stadtmitte.json
deleted file mode 100644
index 705110f615ae5c740aa330f43ba3b920c8851171..0000000000000000000000000000000000000000
--- a/3DGeoVolumes/collections/Stuttgart/Stuttgart_LOD2_Stadtmitte/Stuttgart_LOD2_Stadtmitte.json
+++ /dev/null
@@ -1,62 +0,0 @@
-{
-    "links": [
-      {
-        "rel": "self",
-        "href": "host_url/collections/Stuttgart/Stuttgart_LOD2_Stadtmitte",
-        "type": "application/json",
-        "title": "Stuttgart LOD 2 3D models"
-      }
-    ],
-    "collections": [
-        {
-            "id": "Stuttgart_LOD2_Stadtmitte",
-            "title": "Stuttgart 3D Models LOD2 Stadtmitte Demo",
-            "description": "All Supported 3D Containers for the city of Stuttgart 3D Models LOD2 Stadtmitte",
-            "collectiontype": "3d-container",
-            "extent": {
-              "spatial": {
-                "bbox": [
-                  [9.161434,48.771841,-10,9.183426,48.786318,550]
-                ],
-                "crs": "http://www.opengis.net/def/crs/OGC/0/CRS84h"
-              }
-            },
-            "links": [
-              {
-                "rel": "collections",
-                "href": "host_url/collections/",
-                "type": "application/json"
-              },
-              {
-                "title": "Stuttgart LOD2 Stadtmitte - Collections",
-                "rel": "self",
-                "href": "host_url/collections/Stuttgart/Stuttgart_LOD2_Stadtmitte",
-                "type": "application/json"
-              },
-              {
-                "title": "Stuttgart LOD2 Stadtmitte : 3D Tiles",
-                "rel": "items",
-                "href": "http://193.196.37.89:8092/AssetsHFT/3DTile_Stuttgart_City_LoD2_InnenStadt_ClampToGround/tileset.json",
-                "type": "application/json+3dtiles"
-              }
-            ],
-            "children": [
-              
-            ],
-            "content": [
-              {
-                "title": "Stuttgart LOD2 Stadtmitte - Collections",
-                "rel": "original",
-                "href": "host_url/collections/Stuttgart/Stuttgart_LOD2_Stadtmitte",
-                "type": "application/json"
-              },
-              {
-                "title": "Stuttgart LOD2 Stadtmitte : 3D Tiles",
-                "rel": "original",
-                "href": "http://193.196.37.89:8092/AssetsHFT/3DTile_Stuttgart_City_LoD2_InnenStadt_ClampToGround/tileset.json",
-                "type": "application/json+3dtiles"
-              }
-            ]
-          }
-    ]
-  }
\ No newline at end of file
diff --git a/3DGeoVolumes/collections/Stuttgart/node.md b/3DGeoVolumes/collections/Stuttgart/node.md
new file mode 100644
index 0000000000000000000000000000000000000000..a5d7533ed12ff0f07c1c4bfdc35a0d9a94bc5ea7
--- /dev/null
+++ b/3DGeoVolumes/collections/Stuttgart/node.md
@@ -0,0 +1 @@
+Note: The 3D contents in Stuttgart collections are hosted on another server. In this case, the HREF link is described in the `collections.json` file 
\ No newline at end of file
diff --git a/server.js b/server.js
index 60b4f6480954bf72fdee7969f3f93da7a72450dd..7a98ee42197e87111a5ad2c11c209473ed12b14b 100644
--- a/server.js
+++ b/server.js
@@ -145,7 +145,27 @@
     app.get('/collections/:collectionsId', function (req, res) {
         try {
             var collection_json = require(`./3DGeoVolumes/collections/${req.params.collectionsId}/${req.params.collectionsId}.json`)
-            res.json(collection_json);
+            var collection_resource = require('./3DGeoVolumes/collections/collections.json')
+            var collection_resource_updated = replace_server_url(collection_resource)
+            var selected_collection_byID = []
+            for (let index = 0; index < collection_resource_updated.collections.length; index++) {
+                if (collection_resource_updated.collections[index]["id"] == req.params.collectionsId) {
+                    selected_collection_byID.push(collection_resource_updated.collections[index])
+                }
+            }
+            var selected_collection = {
+                "links": [
+                  {
+                    "rel": "self",
+                    "href": `host_url/collections/${req.params.collectionsId}`,
+                    "type": "application/json",
+                    "title": `OGC API - 3D GeoVolumes collections of ${req.params.collectionsId}`
+                  }
+                ],
+                "collections": selected_collection_byID
+            }
+            selected_collection = replace_server_url(selected_collection)
+            res.json(selected_collection);
         } catch (error) {
             console.log(error)
             res.send("internal error")