An Adoption Petition must be filed in the Circuit Court of the county or city where the Petitioners live. However, if the child was placed by an agency, the petition may be filed in the county or city where the agency is located.
An exception to this general rule allows the petition to be filed where the birth parents gave and executed their consents. This is allowed if the adoption was a parental placement and at least one birth parent appeared in the Juvenile and Domestic Relations District Court to give consent.
This exception usually only applies to cases where the adoptive parents live in a state other than Virginia, as adoptive parents would rarely want to file in any jurisdiction other than where they live.
Virginia Adoption Law does allow non-residents to file in Virginia if the birth parents live in Virginia.
Since the state of Virginia requires a substantial amount of legal work, it's often easier and less expensive for non-resident petitioners to finalize in Virginia in such cases.