Reference:
http://wiki.openstreetmap.org/wiki/ Slippy_map_tilenames#Zoom_levels
Brief overview:
OSM tiles are 256x256 pixel PNG files.
Filename (URL) format is http://tile.openstreetmap.org/zoom/x/y.png
where
zoom=zoom-level-integer (from 0 to 19),
x=longitude-locator-integer (non-negative column number),
y=latitude-locator-integer (non-negative row number).
In the link above, see sample code to calculate x and y for a given zoom-level and a given latitude and longitude.
The following Maui Island map
is done with map tiles at OSM zoom level 12.
Approximate latitude,longitude of Maui:
20.7983 , -156.3319 degrees
Each OSM tile is a 256x256 PNG file.
Each zoom-level-12 tile is one image out of
2^12 x 2^12 = 4096 x 4096 = 16,777,216 images ~ 16 million images
which are used by OpenStreetMap to cover most of the Earth.
These zoom-level-12 tiles go from
x-numbers 265 to 273. (9 columns)
These zoom-level-12 tiles go from
y-numbers 1802 to 1807. (7 rows)
Total: 9 x 7 = 63 tiles
Image width: 9 x 256 = 2,304 pixels
Image height: 7 x 256 = 1,792 pixels
These tiles are fetched from the
OSM server when you (re)load this page.
So these tiles form an image using
the latest versions of the OSM tiles.
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This link provides the map in a
*SINGLE* 2304x1792 pixel PNG file
--- created from OSM tiles
as they existed on 19 Feb 2018.
After you access that link,
you can right-click on the image and
use a popup menu option such as
'Save Image As ...' to save the single
image file to your local file system.
This image file was created with a
Tcl-Tk 'tkGooies' script
in the
'MAPtools' group of 'tkGooie' scripts at the
Freedom Environment software web site.
Here is a link to an OSM (openstreetmap.org)
'slippy map'
for
Maui (Wikipedia link) --- initially at zoom-level 12 and
centered at latitude and longitude 20.7983 -156.3319,
which is near the center of the island.
Page was created 2018 Feb 19.
Page was changed 2018 Jul 08.
(Added 'slippy map' link.)
Page was changed 2019 Jan 11.
(Added css and javascript to try to handle text-size
for smartphones, esp. in portrait orientation.)
Page was changed 2019 Feb 10.
(HTML changes due to reorg of OSMmaps.)