diff --git a/ctod/core/cog/cog_reader_mosaic.py b/ctod/core/cog/cog_reader_mosaic.py
new file mode 100644
index 0000000..95ea96b
--- /dev/null
+++ b/ctod/core/cog/cog_reader_mosaic.py
@@ -0,0 +1,130 @@
+import time
+import requests
+import asyncio
+
+from morecantile import TileMatrixSet, Tile, BoundingBox
+from rio_tiler.mosaic import mosaic_reader
+from rio_tiler.models import ImageData
+from typing import Any
+from urllib.parse import urlparse, urljoin
+from rio_tiler.errors import TileOutsideBounds
+
+class CogReaderMosaic:
+    """A reader for a Cloud Optimized GeoTIFF. This class is used to pool readers to 
+    avoid opening and closing the same file many times.
+    """
+    
+    def __init__(self, pool, cog: str, tms: TileMatrixSet, unsafe: bool = False):
+        self.pool = pool
+        self.cog = cog
+        self.tms = tms
+        self.unsafe = unsafe
+        self.last_used = time.time()
+        self._download_json(cog)
+        
+    def close(self):
+        """Close the reader."""
+        
+        self.rio_reader.close()
+        
+    def tiler(self, src_path: str, *args, **kwargs) -> ImageData:
+        future = asyncio.run_coroutine_threadsafe(self.pool.get_reader(src_path, self.tms), args[3])
+        reader = future.result()
+        
+        data = reader.download_tile(args[0], args[1], args[2], args[3], **kwargs)
+        reader.return_reader()
+                
+        if not data:
+            raise TileOutsideBounds
+            
+        return data
+        
+    def download_tile(self, x: int, y: int, z: int, loop: asyncio.AbstractEventLoop, resampling_method="bilinear", **kwargs: Any) -> ImageData:
+        """Retrieve an image from a Cloud Optimized GeoTIFF based on a tile index.
+
+        Args:
+            tms (TileMatrixSet): The tile matrix set to use.
+            x (int): x tile index.
+            y (int): y tile index.
+            z (int): z tile index.
+            geotiff_path (str): Path or URL to the Cloud Optimized GeoTIFF.
+            resampling_method (str, optional): RasterIO resampling algorithm. Defaults to "bilinear".
+            kwargs (optional): Options to forward to the `rio_reader.tile` method.
+
+        Returns:
+            ImageData: Image data from the Cloud Optimized GeoTIFF.
+        """
+        
+        tile_bounds = self.tms.xy_bounds(Tile(x=x, y=y, z=z))
+        datasets = self._get_intersecting_datasets(tile_bounds)
+        
+        #logging.info(f"{z} {x} {y} {len(datasets)}\n {datasets} \n {tile_bounds}")
+        
+        if not self._tile_intersects(tile_bounds, self.dataset["extent"]) or len(datasets) == 0:
+            return None
+        
+        kwargs["resampling_method"] = resampling_method
+
+        try:
+            img, _ = mosaic_reader(datasets, self.tiler, x, y, z, loop, **kwargs)
+            return img
+        except Exception as e:
+            #logging.warning(f"Failed to load tile {self.cog} {z,x,y}, {e}")
+            return None   
+            
+    def return_reader(self):
+        """Done with the reader, return it to the pool."""
+        
+        self.last_used = time.time()
+        self.pool.return_reader(self)
+
+    def _get_intersecting_datasets(self, tile_bounds: BoundingBox) -> list:
+        intersecting_datasets = []
+        for dataset in self.dataset["datasets"]:
+            if self._tile_intersects(tile_bounds, dataset["extent"]):
+                intersecting_datasets.append(dataset["path"])
+                    
+        return intersecting_datasets
+                
+    def _tile_intersects(self, tile_bounds: BoundingBox, dataset_bounds: list) -> bool:
+        """Check if a tile intersects with a dataset.
+        Instead of check if inside we check if something is outside and 
+        exit early to save some calculation time.
+
+        Args:
+            tile_bounds (morecantile.BoundingBox): The bounds of the tile
+            dataset_bounds (list): The bounds of the dataset.
+
+        Returns:
+            bool: True if bounds intersect, False otherwise
+        """
+        
+        if (tile_bounds.left > dataset_bounds[2] or tile_bounds.right < dataset_bounds[0] or
+            tile_bounds.bottom > dataset_bounds[3] or tile_bounds.top < dataset_bounds[1]):
+            return False
+        
+        return True
+    
+    def _download_json(self, json_url):
+        # Download the JSON file
+        response = requests.get(json_url)
+
+        # Load the JSON content
+        datasets_json = response.json()
+        
+        # Extract base URL
+        base_url = self._get_base_url(json_url)
+        
+        # Extract datasets and their geometries
+
+        for dataset in datasets_json["datasets"]:
+            path = dataset['path']
+            absolute_path = urljoin(base_url, path)
+            dataset["path"] = absolute_path            
+        
+        #self.dataset = datasets_json["info"]
+        self.dataset = datasets_json
+        
+    def _get_base_url(self, url):
+        parsed_url = urlparse(url)
+        return f"{parsed_url.scheme}://{parsed_url.netloc}"
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