Qeydar, Iran
This category belongs to those prophets that are not mentioned either in Islamic Scriptures or in any of the Ahl-e-kitab books. These prophets were mainly sent to different nations around the world including nation of Bani Israel and not much information is available regarding them to us.
Only thing we know is that people revere and regard these sites as prophetic graves from centuries as it was passed onto them from generations so the thing we can go is pass this legacy to our next generation and not take it upon ourselves to decide whether these sites are authentic or not. Cause it is nearly impossible to be a perfect judge of that.
For example there are some prophets whose names aren’t even knows to general public. Only we know from traditional sources of people who were inspired by some Awliyas or by seeing some dreams over and over that there at a certain distance lies the grave of a holy prophet. Perfect example of this is the 8 graves of Prophets found in Sirhind, Punjab (India) by local farmers.
Another Example: Tomb of Prophet Shu’ayb al-Haduri عليه السلام
Coordinates: 36.116445, 48.585874