diff --git a/src/dem.rs b/src/dem.rs
new file mode 100644
index 0000000..719a304
--- /dev/null
+++ b/src/dem.rs
@@ -0,0 +1,53 @@
+
+
+use gdal::errors::GdalError;
+use gdal::Dataset;
+use gdal;
+
+fn get_filename_from_latlon(lat: f64, lon: f64) -> String {
+        // Calculate the rounded values for latitude and longitude
+    let rounded_lat = lat.floor();
+    let rounded_lon = lon.floor();
+
+    // Convert the rounded values to strings with leading zeros if necessary
+    let lat_deg = format!("{:02}", rounded_lat.abs());
+    let lon_deg = format!("{:03}", rounded_lon.abs());
+
+    // Determine the hemisphere prefixes for latitude and longitude
+    let lat_prefix = if rounded_lat >= 0.0 { "N" } else { "S" };
+    let lon_prefix = if rounded_lon >= 0.0 { "E" } else { "W" };
+
+    // Construct the filename
+    let filename = format!(
+        "Copernicus_DSM_30_{}{}_00_{}{}_00_DEM.tif",
+        lat_prefix, lat_deg, lon_prefix, lon_deg
+    );
+
+    filename
+
+}
+
+fn geo_to_pixel(dataset: &Dataset, lat: f64, lon: f64) -> Result<(isize, isize), GdalError> {
+    let transform = dataset.geo_transform()?;
+    let x_pixel = ((lon - transform[0]) / transform[1]).round() as isize;
+    let y_pixel = ((lat - transform[3]) / transform[5]).round() as isize;
+    Ok((x_pixel, y_pixel))
+}
+
+pub fn elevation_from_coordinates(lat: f64, lon: f64) -> f64 {
+    let file = get_filename_from_latlon(lat, lon);
+    let full_filename = format!("data/{file}");
+
+    println!("file for {lat} {lon} is {full_filename}");
+
+    let ds = Dataset::open(full_filename).unwrap();
+    println!("This {} is in '{}' and has {} bands.", ds.driver().long_name(), ds.spatial_ref().unwrap().name().unwrap(), ds.raster_count());
+    println!("PRojection: {}", ds.projection());
+
+
+    let (px, py) = geo_to_pixel(&ds, lat, lon).unwrap();
+
+    let raster_band = ds.rasterband(1).unwrap();
+    let raster_value = raster_band.read_as::<f64>((px, py), (1, 1), (1, 1), None).unwrap();
+    raster_value.data[0]
+}
\ No newline at end of file
diff --git a/src/main.rs b/src/main.rs
index 9a97e70..18a43c0 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,60 +1,8 @@
-use std::fmt::Error;
 
-use gdal::errors::GdalError;
-use gdal::Dataset;
-use gdal;
+mod dem;
+use crate::dem::elevation_from_coordinates;
 
 
-
-
-fn get_filename_from_latlon(lat: f64, lon: f64) -> String {
-        // Calculate the rounded values for latitude and longitude
-    let rounded_lat = lat.floor();
-    let rounded_lon = lon.floor();
-
-    // Convert the rounded values to strings with leading zeros if necessary
-    let lat_deg = format!("{:02}", rounded_lat.abs());
-    let lon_deg = format!("{:03}", rounded_lon.abs());
-
-    // Determine the hemisphere prefixes for latitude and longitude
-    let lat_prefix = if rounded_lat >= 0.0 { "N" } else { "S" };
-    let lon_prefix = if rounded_lon >= 0.0 { "E" } else { "W" };
-
-    // Construct the filename
-    let filename = format!(
-        "Copernicus_DSM_30_{}{}_00_{}{}_00_DEM.tif",
-        lat_prefix, lat_deg, lon_prefix, lon_deg
-    );
-
-    filename
-
-}
-
-fn geo_to_pixel(dataset: &Dataset, lat: f64, lon: f64) -> Result<(isize, isize), GdalError> {
-    let transform = dataset.geo_transform()?;
-    let x_pixel = ((lon - transform[0]) / transform[1]).round() as isize;
-    let y_pixel = ((lat - transform[3]) / transform[5]).round() as isize;
-    Ok((x_pixel, y_pixel))
-}
-
-fn elevation_from_coordinates(lat: f64, lon: f64) -> f64 {
-    let file = get_filename_from_latlon(lat, lon);
-    let full_filename = format!("data/{file}");
-
-    println!("file for {lat} {lon} is {full_filename}");
-
-    let ds = Dataset::open(full_filename).unwrap();
-    println!("This {} is in '{}' and has {} bands.", ds.driver().long_name(), ds.spatial_ref().unwrap().name().unwrap(), ds.raster_count());
-    println!("PRojection: {}", ds.projection());
-
-
-    let (px, py) = geo_to_pixel(&ds, lat, lon).unwrap();
-
-    let raster_band = ds.rasterband(1).unwrap();
-    let raster_value = raster_band.read_as::<f64>((px, py), (1, 1), (1, 1), None).unwrap();
-    raster_value.data[0]
-}
-
 fn main() {
     let lat = 46.6;
     let lon = 6.;