Can a kohen enter the Taj Mahal? When visiting India is a kohen allowed to enter even certain parts of the Taj Mahal? The tombs themselves are of non-Jews, of course, and they are buried beneath the earth.
This is taken from a different question (Issues of Tumah vis a vis non-Jewish human remains)
Original source DO THE REMAINS OF A NON-JEW CONVEY TUMAT MET?
The remains of a non-Jew convey tumas meis if they are touched or carried. Although all agree that the halacha is that the remains of a non-Jew convey tumah through touching and carrying, there is a dispute as to whether the remains of a non-Jew convey tumas ohel. The Shulchan Aruch rules that it is proper to be stringent (Yoreh Deah 372:2).
Therefore it seems as though it is proper (according to the Shulchan Aruch) for a Kohen to be stringent and avoid the Taj Mahal as it represents an "ohel" for a corpse. As always, one should consult their LOR.