diff --git a/Cargo.toml b/Cargo.toml
new file mode 100644
index 0000000..fbc3a2d
--- /dev/null
+++ b/Cargo.toml
@@ -0,0 +1,21 @@
+[package]
+name = "read_osm"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+anyhow = "1.0"
+clap = { version = "4.1", features = ["derive"] }
+flatgeobuf = "3.24"
+geo = { version = "0.26", features = ["use-serde"] }
+geozero = "0.10"
+hashbrown = { version = "0.14", features = ["serde"] }
+log = "0.4"
+once_cell = "1.18"
+osmpbfreader = "0.16"
+serde = { version = "1.0", features = ["derive"] }
+serde_json = "1.0"
+simplelog = "0.12"
+smartstring = { version = "1.0", features = ["serde"] }
diff --git a/src/main.rs b/src/main.rs
new file mode 100644
index 0000000..68462ee
--- /dev/null
+++ b/src/main.rs
@@ -0,0 +1,188 @@
+use anyhow::Result;
+use clap::Parser;
+use flatgeobuf::{ColumnType, FgbCrs, FgbWriter, FgbWriterOptions, GeometryType};
+use geo::{point, Contains, Geometry, Polygon};
+use geozero::{ColumnValue, PropertyProcessor};
+use hashbrown::{HashMap, HashSet};
+use log::{info, LevelFilter};
+use once_cell::sync::Lazy;
+use osmpbfreader::{NodeId, OsmObj, OsmPbfReader, Way};
+use serde::Deserialize;
+use simplelog::{ColorChoice, Config, TermLogger, TerminalMode};
+use smartstring::{LazyCompact, SmartString};
+use std::{
+    fs::File,
+    io::{BufReader, BufWriter, Read, Write},
+    path::PathBuf,
+};
+
+static VALID_ACCESS_TAGS: Lazy<HashSet<&'static str>> = Lazy::new(|| {
+    let mut s = HashSet::new();
+    s.insert("yes");
+    s.insert("permisive");
+    s.insert("destination");
+    s
+});
+
+/// Convert an OpenStreetMap file into a road-network file readable by Metropolis.
+#[derive(Parser, Debug)]
+#[command(author, version, about, long_about)]
+struct Args {
+    /// Path to the input .osm.pbf file.
+    #[arg(long)]
+    osm_file: PathBuf,
+    /// Path to the JSON file with the parameters.
+    #[arg(long)]
+    parameters: PathBuf,
+}
+
+#[derive(Clone, Debug, Default, Deserialize)]
+struct Parameters {
+    /// Polygon representing the area to clip (in EPSG:4326).
+    boundary: Option<Polygon>,
+    /// Set of highway tags to filter.
+    valid_highways: HashSet<SmartString<LazyCompact>>,
+}
+
+fn is_valid_highway(way: &Way, parameters: &Parameters) -> bool {
+    let has_access =
+        VALID_ACCESS_TAGS.contains(way.tags.get("access").map(|s| s.as_str()).unwrap_or("yes"));
+    let is_valid_highway = way
+        .tags
+        .get("highway")
+        .map(|t| parameters.valid_highways.contains(t))
+        .unwrap_or(false);
+    way.nodes.len() >= 2 && has_access && is_valid_highway
+}
+
+fn main() -> Result<()> {
+    let args = Args::parse();
+
+    TermLogger::init(
+        LevelFilter::Info,
+        Config::default(),
+        TerminalMode::Mixed,
+        ColorChoice::Auto,
+    )
+    .expect("Failed to initialize logging");
+
+    info!("Reading OSM file");
+    let file = File::open(&args.osm_file)
+        .unwrap_or_else(|_| panic!("Cannot open file: {:?}", args.osm_file));
+    let buf = BufReader::new(file);
+    let mut pbf = OsmPbfReader::new(buf);
+
+    info!("Reading parameters");
+    let mut bytes = Vec::new();
+    File::open(&args.parameters)
+        .unwrap_or_else(|_| panic!("Cannot open file: {:?}", args.parameters))
+        .read_to_end(&mut bytes)
+        .unwrap_or_else(|_| panic!("Cannot read file: {:?}", args.parameters));
+    let parameters: Parameters =
+        serde_json::from_slice(&bytes).expect("Unable to parse parameters");
+
+    // Find all the nodes and ways that we need to keep.
+    //
+    // A node is valid if all the following conditions are met:
+    // - The node is part of at least two valid ways OR it is the first or last node of a valid
+    // way.
+    // - The node is inside the boundary to clip (if any).
+    let mut valid_ways = HashSet::new();
+    let mut source_target_nodes: HashSet<NodeId> = HashSet::new();
+    let mut all_nodes_count: HashMap<NodeId, usize> = HashMap::new();
+    for obj in pbf.par_iter().filter_map(|r| r.ok()) {
+        if let OsmObj::Way(way) = obj {
+            if is_valid_highway(&way, &parameters) {
+                valid_ways.insert(way.id);
+                source_target_nodes.insert(way.nodes[0]);
+                source_target_nodes.insert(way.nodes[way.nodes.len() - 1]);
+                for &node_id in way.nodes.iter() {
+                    *all_nodes_count.entry(node_id).or_default() += 1;
+                }
+            }
+        }
+    }
+
+    let nodes_to_keep: HashSet<NodeId> = source_target_nodes
+        .into_iter()
+        .chain(
+            all_nodes_count
+                .into_iter()
+                .filter_map(|(k, v)| if v >= 2 { Some(k) } else { None }),
+        )
+        .collect();
+
+    // Find the nodes inside the boundary.
+    let mut valid_nodes: HashSet<NodeId> = HashSet::new();
+    pbf.rewind().unwrap();
+    for obj in pbf.par_iter().filter_map(|r| r.ok()) {
+        if let OsmObj::Node(node) = obj {
+            if nodes_to_keep.contains(&node.id) {
+                let point = point!(x: node.lon(), y: node.lat());
+                if parameters
+                    .boundary
+                    .as_ref()
+                    .map(|b| b.contains(&point))
+                    .unwrap_or(true)
+                {
+                    valid_nodes.insert(node.id);
+                }
+            }
+        }
+    }
+
+    println!("Number of nodes to keep: {}", valid_nodes.len());
+
+    // Store all the nodes that we keep in a FlatGeoBuf with their coordinates.
+    let options = FgbWriterOptions {
+        write_index: true,
+        crs: FgbCrs {
+            code: 4326,
+            ..Default::default()
+        },
+        ..Default::default()
+    };
+    let mut fgb = FgbWriter::create_with_options("nodes", GeometryType::Point, options).unwrap();
+    fgb.add_column("fid", ColumnType::Long, |_fbb, col| {
+        col.nullable = false;
+        col.unique = true;
+    });
+
+    pbf.rewind().unwrap();
+    for obj in pbf.par_iter().filter_map(|r| r.ok()) {
+        if let OsmObj::Node(node) = obj {
+            if nodes_to_keep.contains(&node.id) {
+                fgb.add_feature_geom(
+                    Geometry::Point(point!(x: node.lon(), y: node.lat())),
+                    |feat| {
+                        feat.property(0, "fid", &ColumnValue::Long(node.id.0))
+                            .unwrap();
+                    },
+                )
+                .unwrap();
+            }
+        }
+    }
+
+    let output_path = "../../../output/road_network/france-nodes.fgb";
+    let mut fout = BufWriter::new(File::create(output_path).expect("Cannot create output file"));
+    fgb.write(&mut fout).unwrap();
+
+    pbf.rewind().unwrap();
+    let mut tags: HashMap<SmartString<LazyCompact>, usize> = HashMap::new();
+    for obj in pbf.par_iter().filter_map(|r| r.ok()) {
+        if let OsmObj::Way(way) = obj {
+            if valid_ways.contains(&way.id) {
+                for (key, _value) in way.tags.iter() {
+                    *tags.entry(key.clone()).or_default() += 1;
+                }
+            }
+        }
+    }
+
+    let buf = serde_json::to_vec(&tags)?;
+    let mut file = BufWriter::new(File::open("tmp.json")?);
+    file.write_all(&buf)?;
+
+    Ok(())
+}
diff --git a/src/parameters.json b/src/parameters.json
new file mode 100644
index 0000000..7c0912c
--- /dev/null
+++ b/src/parameters.json
@@ -0,0 +1,18 @@
+{
+  "valid_highway": [
+    "motorway",
+    "trunk",
+    "primary",
+    "secondary",
+    "motorway_link",
+    "trunk_link",
+    "primary_link",
+    "secondary_link",
+    "tertiary",
+    "tertiary_link",
+    "residential",
+    "living_street",
+    "unclassified",
+    "road"
+  ]
+}