Historical map of the area
Blue arrows illustrate the strait's
Traffic Separation Scheme.
Strait of Hormuz ( - Madīq Hurmuz, -
Tangeh-ye Hormoz) is a narrow, strategically important
waterway between the Gulf of
Oman in the southeast and the Persian Gulf. On the north coast is Iran and on the
south coast is the United Arab Emirates and Musandam, an exclave of Oman.
Map of Strait of Hormuz with maritime
political boundaries (2004)
at its narrowest is wide.
It is the
only sea passage to the open ocean for large areas of the petroleum-exporting Persian Gulf.
According to the U.S. Energy Information
, an average of about 15 tankers carrying 16.5 to
17 million barrels
of crude oil normally pass
through the strait every day, making it one of the world's most
strategically important choke points
This represents 40% of the world's seaborne oil shipments, and 20%
of all world shipments.
Ships moving through the Strait follow a Traffic Separation Scheme
(TSS), which separates inbound from outbound traffic to reduce the
risk of collision. The traffic lane is six miles (10 km) wide,
including two two-mile (3 km)-wide traffic lanes, one inbound
and one outbound, separated by a two-mile (3 km) wide
To traverse the Strait, ships pass through the territorial waters
of Iran and Oman under the transit
provisions of the United Nations
Convention on the Law of the Sea
. Although not all countries
have ratified the convention, most countries, including the U.S.,
accept these customary navigation rules as codified in the
Convention.Oman has a radar site LQI to monitor the TSS in the
strait of Hormuz. This site is located on a small island on the
peak of Mussandam Peninsula.
The opening to the Persian Gulf was described, but not given a
name, in the Periplus
of the Erythraean Sea
, a 1st-century mariner's
- Ch.35. At the upper end of these Calaei islands is a range of
mountains called Calon, and there follows not far beyond, the mouth
of the Persian Gulf, where there is much diving for the
pearl-mussel. To the left of the straits are great mountains called
Asabon, and to the right there rises in full view another round and
high mountain called Semiramis; between them the passage across the
strait is about six hundred stadia; beyond which that very great
and broad sea, the Persian Gulf, reaches far into the interior. At
the upper end of this gulf there is a market-town designated by law
called Apologus, situated near Charaex Spasini and the River
There are two opinions about the etymology of this name. In popular
belief the derivation is from the name of the Persian God
(a variant of Ahura
). Compare the Pillars of Hercules at the entrance to the Mediterranean.
Scholars, historians and linguists derive the name "Ormuz" from the
meaning datepalm. In the local dialects of Hurmoz
and Minab this strait is still called Hurmogh and has the
Operation Praying Mantis
On 18 April 1988, the U.S. Navy waged a one-day battle against
Iranian forces in and around the strait. The battle, dubbed
Operation Praying Mantis
the U.S. side, was launched in retaliation for the 14 April
mining of the USS Samuel B.
(FFG-58). U.S. forces sank two Iranian warships, Joshan
and as many as six armed speedboats in the
The downing of Iran Air 655
On July 3, 1988, 290 people were killed when an Iran Air Airbus A300
passenger jet was shot down over the strait by the United States Navy guided missile cruiser
still a lingering
controversy about the event, a tragedy in aviation history.
Collision between USS Newport News and tanker
On January 10, 2007, the nuclear submarine USS Newport News
traveling submerged, struck M/V Mogamigawa
, a 300,000-ton
Japanese-flagged very large crude tanker
, south of the
Tensions in 2008
2008 US-Iranian naval dispute
A series of naval stand-offs between Iranian speedboats and U.S.
warships in the Strait of Hormuz occurred in December 2007 and
January 2008. U.S. officials accused Iran of harassing and
provoking their naval vessels; Iranian officials denied these
allegations. On January 14, 2008, U.S. naval officials appeared to
contradict the Pentagon version of the Jan. 16 event, in which U.S.
officials said U.S. vessels were near to firing on approaching
Iranian boats. The Navy's regional commander, Vice Admiral Kevin Cosgriff
, said the Iranians had
"neither anti-ship missiles nor torpedoes" and that he "wouldn't
characterize the posture of the US 5th Fleet as afraid of these
On June 29, 2008, the commander of Iran's Revolutionary Guard
Mohammed Jafari, said that if Iran were attacked by Israel or the
United States, it would seal off the Strait of Hormuz, to wreak
havoc in oil markets. This statement followed other more ambiguous
threats from Iran's oil minister and other government officials
that a Western attack on Iran would result in turmoil in oil
In response, Vice Admiral Kevin Cosgriff, commander of the U.S. 5th
Fleet stationed in Bahrain across the Persian Gulf from Iran,
warned that such an action by Iran would be considered an act of
war, and that the U.S. would not allow Iran to effectively hold
hostage nearly a third of the world's oil supply.
On July 8, 2008, Ali Shirazi, a mid-level clerical aide to Iran's
Supreme Leader Ayatollah Ali
, was quoted by the student news agency ISNA
as saying to Revolutionary Guards, "The Zionist
regime is pressuring White House officials to attack Iran. If they
commit such a stupidity, Tel Aviv and U.S. shipping in the Persian
Gulf will be Iran's first targets and they will be burned."
An article in International Security contended that Iran could seal
off or impede traffic in the Strait for a month, and an attempt by
the U.S. to reopen it would likely escalate the conflict. In a
later issue, however, the journal published a response which
questioned some key assumptions and suggested a much shorter
timeline for re-opening.
Naval activity in 2008
In the last week of July 2008, in the Operation Brimstone, dozens
of U.S. and foreign navy ships came to off the eastern coast in the
U.S., to undergo joint exercises for possible military activity in
the shallow waters off the coast of Iran.
As of August 11, 2008, more than 40 U.S. and allied ships
reportedly were en route to the Straits of Hormuz. One U.S. carrier
battle group from Japan would complement two more, which are
already in the Persian Gulf, for a total of five battle groups, not
Collision between USS Hartford and USS New Orleans
On March 20, 2009, the USS Hartford collided with the USS New Orleans in the strait. The collision mildly injured 15 sailors aboard the Hartford and ruptured a fuel tank aboard the New Orleans, spilling 25,000 gallons of marine diesel fuel.