Paul H. Seely’s Genesis-based estimate of the entire extent of the then – known world, as given below, accords perfectly with my own estimate of it, as I have argued in:
“We should perhaps stop, however, to note just how large the earth was understood to be by the biblical writer. The extent of the earth in the understanding of the biblical writer is given in Gen 10. The northern boundary is marked by the peoples around the Black Sea (Gen 10:2; Ezek 38:6). The southern boundary is marked by peoples living in the extreme south of the Arabian peninsula (Gen 10:7: cf. Matt 12:42). The eastern boundary is marked by Elam (Gen 10:22). The western boundary is at Tarshish (Gen 10:4), but its location is not certain. Although elsewhere in Scripture Tarshish may refer to Tartessos in Spain, in Gen 10 it probably refers to a location c. latitude ten degrees east, perhaps Sardinia, Tunis, or Carthage. “All the earth” in Gen 11:1 is then a circle or ellipse around 2400 miles in width and 1200 in height.53 Everyone in the ancient Near East understood this circular area to be the entire extent of the earth and that this earth was surrounded by a great ocean.54 …”.