diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index d005f307..1eec918d 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -43,7 +43,7 @@ jobs:
 
     steps:
       - name: Checkout source code
-        uses: actions/checkout@v2
+        uses: actions/checkout@v4
 
       - name: Create .env file
         uses: noi-techpark/github-actions/env-file@v2
@@ -104,6 +104,14 @@ jobs:
       - name: use mobility.api.opendatahub.testingmachine.eu for testing
         run: sed -i 's/mobility.api.opendatahub.com/mobility.api.opendatahub.testingmachine.eu/' */config.yml
 
+      - name: Cache OSM and elevation data
+        uses: actions/cache@v4
+        with:
+          path: |
+            data/italy-nord-est.osm.pbf
+            data/srtm*
+          key: input-data
+
       - name: Build graph
         run: sh build-graph.sh 
 
diff --git a/build-graph.sh b/build-graph.sh
index ab2af0ff..9e02216b 100755
--- a/build-graph.sh
+++ b/build-graph.sh
@@ -19,13 +19,16 @@ OTP_IMAGE=docker.io/opentripplanner/opentripplanner:2.5.0_2024-01-19T14-50
 
 # when on github actions then install the required tools
 if [ -n "${CI+isset}" ]; then
-  sudo apt-get -qq install osmium-tool wget
+  sudo apt-get -qq install osmium-tool pyosmium wget
 fi
 
 mkdir -p data
 
 if [ ! -f "${NORTH_EAST_PBF}" ]; then
   ${WGET} ${NORTH_EAST_URL} -O ${NORTH_EAST_PBF}
+else
+  echo "Checking for updates for existing OSM file"
+  pyosmium-up-to-date ${NORTH_EAST_PBF}
 fi
 
 # cut out South Tyrol from the large North East Italy extract