Get a compass 1 dollar cost.
Go to nearest road that shown in google map. Use the compass on the road to find out direction of the road.

Go open the google map and find out same road, same location. Draw a compass on the road yourself and compare them.

You'll see that some of directions are true but some of aren't. It is your chance to your test prove or disprove the map.
In Piri Reis map Istanbul European side seems as east to west, different direction of Asian side of Istanbul; and according to google it seems as Asian side and placed on East south.


My compass prove the N on Piri reis map is true and N on google map is wrong in west side of Istanbul !
30 cents for disproving round map !

Almost all important religional structures placed the direction to real north ! This situation causes by a bit religinal and a bit climatic.
This is patriarchate. One of the most religinal structure in Istanbul. Also Turkey, and a bit for Europe. One of the most important building for Ortodoxes.

Placed North to 40 degrees east!
This is Aya Irini. One of the most known temple in Istanbul. Placed in Topkapi Palace.

Placed North to 40 degrees East!
This is Suleymaniye. One of two biggest mosque in Istanbul.

Placed North to 40 degrees East!
This is the greatest mosque in Istanbul, also in Turkey. Sultan Ahmet.

Placed North to 40 degrees East!
I'm calculated true north now 25 degrees east. So history have about 15 degrees mistake and google has about 20 degrees mistake. My map has about zero degrees mistake.
