diff --git a/rowers/c2stuff.py b/rowers/c2stuff.py
index ebe1d45b..3d390b6b 100644
--- a/rowers/c2stuff.py
+++ b/rowers/c2stuff.py
@@ -108,9 +108,16 @@ def get_c2_workouts(rower):
         for item in res.json()['data']:
             alldata[item['id']] = item
 
-        knownc2ids = uniqify([
+        knownc2ids = [
             w.uploadedtoc2 for w in Workout.objects.filter(user=rower)
-        ])
+        ]
+
+        tombstones = [
+            t.uploadedtoc2 for t in TombStone.objects.filter(user=rower)
+        ]
+
+        knownc2ids = uniqify(knownc2ids+tombstones)
+        
         newids = [c2id for c2id in c2ids if not c2id in knownc2ids]
 
         for c2id in newids:
diff --git a/rowers/models.py b/rowers/models.py
index 1201fdd6..f3f1eed9 100644
--- a/rowers/models.py
+++ b/rowers/models.py
@@ -2506,7 +2506,6 @@ class PlannedSessionFormSmall(ModelForm):
 boattypes = mytypes.boattypes
     
 # Workout
-@python_2_unicode_compatible
 class Workout(models.Model):
     workouttypes = mytypes.workouttypes
     workoutsources = mytypes.workoutsources
@@ -2611,7 +2610,28 @@ class Workout(models.Model):
             )
             
         return stri
+    
+class TombStone(models.Model):
+    user = models.ForeignKey(Rower,on_delete=models.CASCADE)
+    uploadedtoc2 = models.IntegerField(default=0)
+    uploadedtostrava = models.BigIntegerField(default=0)
+    uploadedtosporttracks = models.BigIntegerField(default=0)
+    uploadedtounderarmour = models.BigIntegerField(default=0)
+    uploadedtotp = models.BigIntegerField(default=0)
+    uploadedtorunkeeper = models.BigIntegerField(default=0)
 
+@receiver(models.signals.pre_delete,sender=Workout)
+def create_tombstone_on_delete(sender, instance, **kwargs):
+    t = TombStone(
+        user=instance.user,
+        uploadedtoc2 = instance.uploadedtoc2,
+        uploadedtostrava = instance.uploadedtostrava,
+        uploadedtounderarmour = instance.uploadedtounderarmour,
+        uploadedtotp = instance.uploadedtotp,
+        uploadedtorunkeeper = instance.uploadedtorunkeeper,
+    )
+    t.save()
+    
 # delete files belonging to workout instance
 # related GraphImage objects should be deleted automatically
 @receiver(models.signals.post_delete,sender=Workout)
diff --git a/rowers/stravastuff.py b/rowers/stravastuff.py
index 15a9a511..87d8f185 100644
--- a/rowers/stravastuff.py
+++ b/rowers/stravastuff.py
@@ -165,9 +165,15 @@ def get_strava_workouts(rower):
                         w.uploadedtostrava = int(stravaid)
                         w.save()
                 
-        knownstravaids = uniqify([
+        knownstravaids = [
             w.uploadedtostrava for w in Workout.objects.filter(user=rower)
-            ])
+            ]
+
+        tombstones = [
+            t.uploadedtostrava for t in TombStone.objects.filter(user=rower)
+            ]
+
+        knownstravaids = uniqify(knownstravaids+tombstones)
         
         newids = [stravaid for stravaid in stravaids if not stravaid in knownstravaids]
 
diff --git a/rowers/tests/testdata/testdata.csv.gz b/rowers/tests/testdata/testdata.csv.gz
index d1090619..46cdd11e 100644
Binary files a/rowers/tests/testdata/testdata.csv.gz and b/rowers/tests/testdata/testdata.csv.gz differ