1. An underground passage or corridor that is accessible to the general public for transportation, pedestrian use, or commercial purposes
The public tunnel connects the subway station to the shopping mall downtown.
O túnel público conecta a estação de metrô ao shopping do centro.
2. A government-owned or municipally-managed underground structure built for public infrastructure and mobility
Workers are maintaining the public tunnel that runs beneath the main boulevard.
Os operários estão mantendo o túnel público que passa sob a avenida principal.