diff --git a/day08/common.rs b/day08/common.rs
new file mode 100644
index 0000000..6fe6037
--- /dev/null
+++ b/day08/common.rs
@@ -0,0 +1,55 @@
+// Copyright 2022 Christian Ulrich
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+use std::io;
+
+pub struct Forest {
+    trees: Vec<Vec<u8>>,
+}
+
+impl Forest {
+    pub fn from_stdin() -> Result<Forest, &'static str> {
+        let mut trees = vec![];
+        for line in io::stdin().lines() {
+            let line = line.unwrap();
+            if line.len() > 0 {
+                trees.push(line.bytes().map(|b| b - '0' as u8).collect());
+            }
+        }
+        Ok(Self { trees: trees })
+    }
+
+    pub fn dimensions(&self) -> (usize, usize) {
+        (self.trees[0].len(), self.trees.len())
+    }
+
+    pub fn tree(&self, x: usize, y: usize) -> Option<u8> {
+        match y < self.trees.len() && x < self.trees[0].len() {
+            false => None,
+            true => Some(self.trees[y][x]),
+        }
+    }
+
+    pub fn line(&self, index: usize) -> Option<impl Iterator<Item = &u8>> {
+        Some(self.trees.get(index)?.iter())
+    }
+
+    pub fn column(&self, index: usize) -> Option<impl Iterator<Item = &u8>> {
+        match self.trees[0].len() > index {
+            false => None,
+            true => Some(self.trees.iter().map(move |line| &line[index])),
+        }
+    }
+}
diff --git a/day08/input b/day08/input
new file mode 100644
index 0000000..d4d4fd0
--- /dev/null
+++ b/day08/input
@@ -0,0 +1,100 @@
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diff --git a/day08/part1.rs b/day08/part1.rs
new file mode 100644
index 0000000..d1eedcd
--- /dev/null
+++ b/day08/part1.rs
@@ -0,0 +1,40 @@
+// Copyright 2022 Christian Ulrich
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+//
+// usage: ./part1 < input
+
+pub mod common;
+
+use common::Forest;
+
+fn main() -> Result<(), &'static str> {
+    let forest = Forest::from_stdin()?;
+    let (x_len, y_len) = forest.dimensions();
+    let mut result = 0;
+    for y in 0..y_len {
+        for x in 0..x_len {
+            let tree = forest.tree(x, y).unwrap();
+            let is_visible = forest.line(y).unwrap().take(x).all(|t| t < &tree)
+                || forest.line(y).unwrap().skip(x + 1).all(|t| t < &tree)
+                || forest.column(x).unwrap().take(y).all(|t| t < &tree)
+                || forest.column(x).unwrap().skip(y + 1).all(|t| t < &tree);
+            if is_visible {
+                result += 1;
+            }
+        }
+    }
+    println!("{result}");
+    Ok(())
+}
diff --git a/day08/testinput b/day08/testinput
new file mode 100644
index 0000000..16d6fbd
--- /dev/null
+++ b/day08/testinput
@@ -0,0 +1,5 @@
+30373
+25512
+65332
+33549
+35390