Waze has announced that it’s expanding its Waze Beacon program to New York City tunnels today, working together with the MTA and Port Authority to improve navigation apps (including Waze, obviously) when underground. The changes start today, with Waze Beacons going live in the Holland Tunnel, Lincoln Tunnel, Queens-Midtown Tunnel, and Hugh L. Carey (Brooklyn-Battery) Tunnel.

Don’t get lost the next time you have to drive into New York

The Waze Beacons themselves are just battery-powered microcontrollers that use low-powered Bluetooth signals to communicate with smartphones, allowing for Waze to provide alternative location services to drivers even when out of GPS range (relying on Google’s near-field Eddystone technology to communicate).

The Beacons are installed on tunnel ways and can be used to ferry information to drivers underground (for privacy reasons, the Beacons only relay information one way), making it possible to alert drivers of sudden changes in traffic or accidents even without GPS.

As Waze points out on its Beacons site, other navigation services take advantage of Waze’s Beacons to offer the same kind of support, too, so in theory you’ll be able to take advantage of the improved service even if you’re not specifically a Waze user.