Each row says what is behind its code before you follow it. Article — the entry is written and has its own page. Brief — no page of its own yet; the link leads to whatever holds it. Register row — the code exists and the entry is not written. The register is wider than the library of written entries, and always will be; this line is here so the interface does not pass one off as the other.
LHL-S-557
Umm ar-Rasas
Register rowRegister row
LHL-S-613
Varanasi
Register rowRegister row
LHL-S-654
Qom
Register rowRegister row
LHL-S-662
Sarnath
Register rowRegister row
LHL-S-663
The Matha
Register rowRegister row