In GLMZ, physical movement is not a right but a function of citizenship tier, corporate affiliation, and credit standing. The city's integrated Transit Credential System (TCS) — managed jointly by the Meridian Surface Authority and the four dominant transit corporations, chiefly OmniPath Holdings and Cascade Mobility Group — gates every formal transit node behind biometric and neural handshake verification. Tier-One and Tier-Two citizens access the full mag-lev spine, aerial drone corridors, and vertical shaft networks without friction; their neural interfaces sync automatically with turnstile infrastructure, and their transit histories are archived but rarely audited. For Tier-Three citizens — the vast majority of Meridian's working population — access is conditional on maintained employment contracts, credit balance, and sector-specific permits. A Tier-Three resident of the Gowanus Shelf industrial district may be physically unable to board a northbound mag-lev toward the Lakefront Corporate Precinct without a destination-specific clearance code issued by their employer or a registered civic sponsor.

The practical consequences of this stratification are visible in the bodies of the city's lower residents. Workers in the sub-grid manufacturing corridors of South Meridian — particularly the Pressed Steel Quarter and the Vance Industrial Flats — routinely walk four to six kilometers each shift because their transit credits have lapsed or because their employer has flagged their account pending contract renewal. The concept of 'dead credit transit' — riding on borrowed or loaned transit credits — exists in a legal gray zone; OmniPath's terms of service prohibit credential sharing, but enforcement is inconsistent, concentrated in high-visibility zones near Tier-One interfaces where the optics of exclusion are most politically sensitive. In the deeper sub-levels, transit enforcers rarely appear, and informal credit pooling among shift workers is quietly tolerated.

For Tier-Four residents and the undocumented population colloquially known as 'Unlisted,' formal transit is essentially inaccessible. The TCS treats an absent or unverified neural handshake as a security event, triggering automated lockout barriers and, in some nodes, alerting MSA transport police. The Unlisted — estimated between 180,000 and 340,000 individuals depending on the methodology, a figure the Meridian Data Governance Office formally disputes — navigate the city through entirely parallel infrastructure: maintenance access tunnels, decommissioned freight shafts, and the informal walking networks documented in the samizdat cartography tradition known as 'ghost mapping.' The Hollowthorn Passage, a six-kilometer sub-basement route connecting the Vance Flats to the Oldtown Remnant district, is the most well-known ghost map corridor, maintained cooperatively by residents who patch its lighting and clear periodic flood debris from the Lake drainage overflow systems.

The psychological dimension of transit stratification is understudied in sanctioned literature but extensively discussed in unlicensed mesh journalism. Residents of the lower tiers describe a form of spatial anxiety — a continuous low-grade awareness of which spaces they are permitted to occupy and the precise conditions under which that permission might be revoked. A missed payroll cycle, a contract dispute, or a credit provider adjustment can reduce a Tier-Three worker's transit access radius by kilometers overnight, effectively stranding them from medical facilities, food distribution hubs, or family members in adjacent districts. Social workers operating through the Meridian Civic Aid Consortium (itself a corporate-adjacent NGO with contested independence) refer to this phenomenon informally as 'radius collapse,' and it appears in intake assessments as a significant precipitating factor in acute housing and food insecurity events.