diff --git a/data/githooks/pre-push b/data/githooks/pre-push
index f055620..2d59c3f 100755
--- a/data/githooks/pre-push
+++ b/data/githooks/pre-push
@@ -37,4 +37,8 @@ echo "Test element generation"
 python3 roentgen.py element --node amenity=bench,material=wood \
     || { echo "FAIL"; exit 1; }
 
+echo "Test tile generation"
+python3 roentgen.py tile --coordinates 46.09498,10.06879 --cache test/data \
+    || { echo "FAIL"; exit 1; }
+
 exit 0
diff --git a/roentgen/osm_getter.py b/roentgen/osm_getter.py
index c737303..17760a8 100644
--- a/roentgen/osm_getter.py
+++ b/roentgen/osm_getter.py
@@ -38,7 +38,7 @@ def get_osm(
 
     content: Optional[bytes] = get_data(
         "api.openstreetmap.org/api/0.6/map",
-        {"bbox": boundary_box},
+        {"bbox": boundary_box.get_format()},
         is_secure=True,
     ).decode("utf-8")
 
diff --git a/roentgen/tile.py b/roentgen/tile.py
index efc8e0a..5c12632 100644
--- a/roentgen/tile.py
+++ b/roentgen/tile.py
@@ -55,7 +55,8 @@ class Tiles:
 
         extended_boundary_box: BoundaryBox = BoundaryBox(
             lon_1, lat_1, lon_2, lat_2
-        )
+        ).round()
+
         return cls(tiles, tile_1, tile_2, scale, extended_boundary_box)
 
     def draw(self, directory: Path, cache_path: Path) -> None:
@@ -68,7 +69,7 @@ class Tiles:
         get_osm(self.boundary_box, cache_path)
 
         map_ = OSMReader().parse_osm_file(
-            cache_path / (self.boundary_box.get_format_rounded() + ".osm")
+            cache_path / (self.boundary_box.get_format() + ".osm")
         )
         for tile in self.tiles:
             file_path: Path = tile.get_file_name(directory)
@@ -86,7 +87,7 @@ class Tiles:
         :param cache_path: directory for temporary SVG file and OSM files
         """
         output_path: Path = cache_path / (
-            self.boundary_box.get_format_rounded() + ".svg"
+            self.boundary_box.get_format() + ".svg"
         )
         if not output_path.exists():
             content = get_osm(self.boundary_box, cache_path)
@@ -95,7 +96,7 @@ class Tiles:
                 return None
 
             map_: Map = OSMReader().parse_osm_file(
-                cache_path / (self.boundary_box.get_format_rounded() + ".osm")
+                cache_path / (self.boundary_box.get_format() + ".osm")
             )
             lat_2, lon_1 = self.tile_1.get_coordinates()
             lat_1, lon_2 = Tile(
@@ -129,9 +130,7 @@ class Tiles:
             with output_path.open("w+") as output_file:
                 svg.write(output_file)
 
-        png_path: Path = (
-            cache_path / f"{self.boundary_box.get_format_rounded()}.png"
-        )
+        png_path: Path = cache_path / f"{self.boundary_box.get_format()}.png"
         if not png_path.exists():
             rasterize(output_path, png_path)
 
@@ -189,14 +188,12 @@ class Tile:
             self.x + 1, self.y + 1, self.scale
         ).get_coordinates()
 
-        # FIXME: check negative values
+        lat_2 = point_1[0]
+        lon_1 = point_1[1]
+        lat_1 = point_2[0]
+        lon_2 = point_2[1]
 
-        lat_2 = int(point_1[0] * 1000) / 1000 + 0.002
-        lon_1 = int(point_1[1] * 1000) / 1000 - 0.001
-        lat_1 = int(point_2[0] * 1000) / 1000 - 0.001
-        lon_2 = int(point_2[1] * 1000) / 1000 + 0.002
-
-        return BoundaryBox(lon_1, lat_1, lon_2, lat_2)
+        return BoundaryBox(lon_1, lat_1, lon_2, lat_2).round()
 
     def load_map(self, cache_path: Path) -> Map:
         """
@@ -208,7 +205,7 @@ class Tile:
         get_osm(boundary_box, cache_path)
 
         return OSMReader().parse_osm_file(
-            cache_path / f"{boundary_box.format()}.osm"
+            cache_path / f"{boundary_box.get_format()}.osm"
         )
 
     def get_file_name(self, directory_name: Path) -> Path:
diff --git a/roentgen/ui.py b/roentgen/ui.py
index dae0ad2..a88ccea 100644
--- a/roentgen/ui.py
+++ b/roentgen/ui.py
@@ -257,16 +257,18 @@ class BoundaryBox:
         """Get right bottom corner of the boundary box."""
         return self.bottom, self.right
 
-    def get_format_rounded(self) -> str:
+    def round(self) -> "BoundaryBox":
         """
-        Get text representation of the boundary box:
-        <longitude 1>,<latitude 1>,<longitude 2>,<latitude 2>.  Coordinates are
-        rounded to three digits after comma.
+        Round boundary box.
         """
-        return (
-            f"{self.left - 0.001:.3f},{self.bottom - 0.001:.3f},"
-            f"{self.right + 0.001:.3f},{self.top + 0.001:.3f}"
-        )
+        # FIXME: check negative values
+
+        self.left = int(self.left * 1000) / 1000 - 0.001
+        self.bottom = int(self.bottom * 1000) / 1000 - 0.001
+        self.right = int(self.right * 1000) / 1000 + 0.002
+        self.top = int(self.top * 1000) / 1000 + 0.002
+
+        return self
 
     def get_format(self) -> str:
         """
diff --git a/test/data/10.066,46.093,10.070,46.097.osm b/test/data/10.066,46.093,10.070,46.097.osm
new file mode 100644
index 0000000..607ae6c
--- /dev/null
+++ b/test/data/10.066,46.093,10.070,46.097.osm
@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<osm version="0.6" generator="CGImap 0.8.5 (2521311 spike-06.openstreetmap.org)" copyright="OpenStreetMap and contributors" attribution="http://www.openstreetmap.org/copyright" license="http://opendatacommons.org/licenses/odbl/1-0/">
+ <bounds minlat="46.0930000" minlon="10.0660000" maxlat="46.0970000" maxlon="10.0700000"/>
+ <node id="534246185" visible="true" version="1" changeset="2872960" timestamp="2009-10-17T13:34:50Z" user="kaitu" uid="69717" lat="46.0949830" lon="10.0687940">
+  <tag k="ele" v="2743"/>
+  <tag k="name" v="Cima Tresciana"/>
+  <tag k="natural" v="peak"/>
+  <tag k="source" v="Regione Lombardia - La banca dati territoriali CTR10000 e' prodotta da Regione Lombardia - Infrastruttura per l'Informazione Territoriale"/>
+ </node>
+</osm>