Fort McHenry Tunnel

Fort McHenry Tunnel
Southbound tunnel, Bore 2
Overview
LocationBaltimore Harbor
Coordinates39°15′39.2″N 76°34′36.3″W / 39.260889°N 76.576750°W / 39.260889; -76.576750
Route I-95
StartLocust Point
EndCanton
Operation
Constructed1980–1985
OpenedNovember 23, 1985 (1985-11-23)
OwnerMaryland Transportation Authority
TrafficAutomotive
CharacterHighway
TollPassenger cars:
$3 Maryland E-ZPass
$4 non-Maryland E-ZPass
$6 Video toll
Vehicles per day115,000
Technical
Length1.5 miles (2.4 km)
No. of lanes8
Operating speed55 miles per hour (89 km/h)
Lowest elevation107 feet (33 m) below harbor water surface
Tunnel clearance13.6 feet (4.1 m)
Width26 feet (7.9 m)
Route map

The Fort McHenry Tunnel is a four-tube, bi-directional tunnel that carries traffic on Interstate 95 (I-95) underneath the Baltimore Harbor. Named for nearby Fort McHenry, the tunnel is the lowest point in the Interstate Highway System under water.

Construction began in May 1980; the tunnel opened on November 23, 1985. Having consumed some $750 million (equivalent to $2.2 billion in 2024), it was the most expensive Interstate project until surpassed by the Big Dig in Boston. As of 2009, it was used by 43.4 million vehicles annually.

Tolls are collected in both directions. The toll for cars is $3 with a Maryland E-ZPass and $4 with another state's E-ZPass. Vehicles without an E-ZPass pay more, as do those with more than two axles—up to $45 for a 6+ axle vehicle without an E-ZPass. All-electronic tolling using E-ZPass or toll-by-plate started in March 2020 as a result of the COVID-19 pandemic and was made permanent in August 2020. A project to demolish the toll plaza and replace it with overhead gantries for open road tolling started in 2022.