diff --git a/gpxtrackposter/cli.py b/gpxtrackposter/cli.py
index b20bc2a..75eadbe 100755
--- a/gpxtrackposter/cli.py
+++ b/gpxtrackposter/cli.py
@@ -193,6 +193,14 @@ def main() -> None:
         default=1.0,
         help="min distance by km for track filter",
     )
+    args_parser.add_argument(
+        "--activity",
+        dest="activity",
+        metavar="ACTIVITY",
+        type=str,
+        default="all",
+        help="Filter tracks by activity; e.g. 'running' (default: all activities)",
+    )
     args_parser.add_argument(
         "--with-animation",
         dest="with_animation",
@@ -228,6 +236,7 @@ def main() -> None:
 
     loader.special_file_names = args.special
     loader.set_min_length(args.min_distance * Units().km)
+    loader.set_activity(args.activity)
     if args.clear_cache:
         print("Clearing cache...")
         loader.clear_cache()
diff --git a/gpxtrackposter/track.py b/gpxtrackposter/track.py
index 85ff0a4..3874983 100644
--- a/gpxtrackposter/track.py
+++ b/gpxtrackposter/track.py
@@ -26,10 +26,11 @@ class Track:
     Attributes:
         file_names: Basename of a given file passed in load_gpx.
         polylines: Lines interpolated between each coordinate.
-        start_time: Activity start time.
-        end_time: Activity end time.
-        length: Length of the track (2-dimensional).
-        self.special: True if track is special, else False.
+        _start_time: Activity start time.
+        _end_time: Activity end time.
+        _length_meters: Length of the track (2-dimensional).
+        special: True if track is special, else False.
+        activity_type: Activity type
 
     Methods:
         load_gpx: Load a GPX file into the current track.
@@ -48,12 +49,14 @@ def __init__(self) -> None:
         # within a thread (which would create a second unit registry!)
         self._length_meters = 0.0
         self.special = False
+        self.activity_type = None
 
     def load_gpx(self, file_name: str, timezone_adjuster: typing.Optional[TimezoneAdjuster]) -> None:
         """Load the GPX file into self.
 
         Args:
-            file_name: GPX file to be loaded .
+            file_name: GPX file to be loaded.
+            timezone_adjuster: timezone adjuster
 
         Raises:
             TrackLoadError: An error occurred while parsing the GPX file (empty or bad format).
@@ -139,6 +142,7 @@ def _load_gpx_data(self, gpx: gpxpy.gpx.GPX, timezone_adjuster: typing.Optional[
             for s in t.segments:
                 line = [s2sphere.LatLng.from_degrees(p.latitude, p.longitude) for p in s.points]
                 self.polylines.append(line)
+        self.activity_type = gpx.tracks[0].type.lower()
 
     def append(self, other: "Track") -> None:
         """Append other track to self."""
diff --git a/gpxtrackposter/track_loader.py b/gpxtrackposter/track_loader.py
index 1e5f25b..600cc1b 100644
--- a/gpxtrackposter/track_loader.py
+++ b/gpxtrackposter/track_loader.py
@@ -53,10 +53,11 @@ class TrackLoader:
     """Handle the loading of tracks from cache and/or GPX files
 
     Attributes:
-        min_length: All tracks shorter than this value are filtered out.
+        _min_length: All tracks shorter than this value are filtered out.
         special_file_names: Tracks marked as special in command line args
         year_range: All tracks outside of this range will be filtered out.
         cache_dir: Directory used to store cached tracks
+        _activity_type: Only gpx files with activity type are considered
 
     Methods:
         clear_cache: Remove cache directory
@@ -71,6 +72,7 @@ def __init__(self, workers: typing.Optional[int]) -> None:
         self.cache_dir: typing.Optional[str] = None
         self.strava_cache_file = ""
         self._cache_file_names: typing.Dict[str, str] = {}
+        self._activity_type: str = "all"
 
     def set_cache_dir(self, cache_dir: str) -> None:
         self.cache_dir = cache_dir
@@ -87,6 +89,9 @@ def clear_cache(self) -> None:
     def set_min_length(self, min_length: pint.quantity.Quantity) -> None:
         self._min_length = min_length
 
+    def set_activity(self, activity_type: str) -> None:
+        self._activity_type = activity_type.lower()
+
     def load_tracks(self, base_dir: str) -> typing.List[Track]:
         """Load tracks base_dir and return as a List of tracks"""
         file_names = list(self._list_gpx_files(base_dir))
@@ -169,7 +174,10 @@ def _filter_and_merge_tracks(self, tracks: typing.List[Track]) -> typing.List[Tr
         # merge tracks that took place within one hour
         tracks = self._merge_tracks(tracks)
         # filter out tracks with length < min_length
-        return [t for t in tracks if t.length() >= self._min_length]
+        tracks = [t for t in tracks if t.length() >= self._min_length]
+        # filter out tracks with wrong activity type
+        tracks = [t for t in tracks if t.activity_type == self._activity_type or self._activity_type == "all"]
+        return tracks
 
     @staticmethod
     def _merge_tracks(tracks: typing.List[Track]) -> typing.List[Track]: