The weirder thing is, Aljiba isn't located near Castlevania.
Aljiba is closest to the Carmilla Cemetery, Joma Marsh, and Dabi's Path. Even years later, a town wouldn't just move on over.
Jova, however, is the closest village to Castlevania, in Simon's Quest. Unfortunately, there is no direct path from Jova to the Castle in Simon's Time.
However, in Richter's time, if the town he visits is actually Jova, and nor Aljiba (probably just a small error in development?), then the Town Expansion to the east, coupled with the underground pathways, could conceivably lead to both the Outer Border to Dracula's Castle Grounds, as well as the Aqueduct Bridge.
Back on Topic, however...
I don't think the Belmonts live in an of the Simon's Quest villages.
I think that some descendants of the Belmont Clan remained in Wygol, while others went out to see the world and hid who they were.
This was my original reason for thinking that the Morrises were actually Belmonts in disguise; not that they were another clan, but a major branch of the clan, renamed in name after Richter's Downfall.
I'm not sure I can go with that theory now, since now there are other games that revealed a few more facts (events in Portrait of Ruin, the existence of Julius Belmont in the Sorrow story, etc.).