A typical cloverleaf interchange with collector/distributor roads.

Many old cloverleaves elongate the ramps in the direction of the surface road. This one has been supplemented with collector/distributor roads.

In the northeast corner of this cloverleaf, a bridge has been added to eliminate weaving.

A cloverleaf interchange is a two-level interchange in which right turns (in countries that drive on the left) are handled by loop ramps. To go right (in left-hand traffic), vehicles first pass either over or under the other road, then turn right onto a one-way three-fourths loop ramp (270°) and merge onto the intersecting road. cloverleaf road junction. ... cloverleaf road junction. ... A collector/distributor road, often abbreviated as C/D road, is a one-way road next to a freeway that is used for some or all of the ramps that would otherwise merge into or split from the main lanes of the freeway. ... This is a file from the Wikimedia Commons, a repository of free content hosted by the Wikimedia Foundation. ... This is a file from the Wikimedia Commons, a repository of free content hosted by the Wikimedia Foundation. ... A collector/distributor road, often abbreviated as C/D road, is a one-way road next to a freeway that is used for some or all of the ramps that would otherwise merge into or split from the main lanes of the freeway. ... Download high resolution version (896x608, 177 KB)This is a file from the Wikimedia Commons, a repository of free content hosted by the Wikimedia Foundation. ... Download high resolution version (896x608, 177 KB)This is a file from the Wikimedia Commons, a repository of free content hosted by the Wikimedia Foundation. ... High-capacity freeway interchange in Los Angeles, California. ... This article covers only rules of highways. ... Vehicles are non-living means of transportation. ...

Cloverleaves were named this way because they resemble the leaves of a four-leaf clover. In botany, a leaf is an above-ground plant organ specialized for photosynthesis. ... The four-leaf clover is a rare mutation of the common three-leaf clover. ...

In the USA, cloverleaf interchanges have existed long before the interstate system. They were originally created for busier interchanges that the original diamond interchange system could not handle. They were used for over 40 years as the US interstate system expanded rapidly. Large transport trucks that exceeded the usual 25 MPH (40 km/h) speed limit too frequently rolled over the side. ("Overturned big-rig on the ramp to..." was and remains a common traffic report on radio.) For this reason, cloverleaf interchanges have become a common point of traffic congestion at busy junctions. Interstate Highways in the lower 48 states. ... A typical diamond interchange. ... The driver of this DAF tractor with an auto-transport semi-trailer prepares to offload Skoda Octavia cars in Cardiff, Wales For further uses of the word truck, see Truck (disambiguation). ... Miles per hour is a unit of speed, expressing the number of international miles covered per hour. ... Kilometre per hour (American spelling: kilometer per hour) is a unit of both speed (scalar) and velocity (vector). ... A speed limit is the maximum speed allowed by law for vehicles on a road. ... semi-trailer truck with sleeper behind the cab. ... In many parts of the world traffic is generally organized, flowing in lanes of travel for a particular direction, with interchanges, traffic signals, or signage at intersections to facilitate the orderly and timely flow of traffic. ...

The first cloverleaves

The cloverleaf was patented in the United States by Arthur Hale, a civil engineer in Maryland, on February 29, 1916.[1] A patent is a set of exclusive rights granted by a government to an inventor or applicant for a limited amount of time (normally maximum 20 years from the filing date, depending on extension). ... The term civil engineer refers to an individual who practices civil engineering. ... State nickname: Old Line State; Free State Official languages None Capital Annapolis Largest city Baltimore Governor Robert L. Ehrlich (R) Senators Paul Sarbanes (D) Barbara Mikulski (D) Area  - Total  - % water Ranked 42nd 32,160 km² 21 Population  - Total (2000)  - Density Ranked 19th 5,296,486 165/km² Admission into Union... February 29 is the 60th day of a leap year in the Gregorian Calendar, with 306 days remaining. ... 1916 (MCMXVI) is a leap year starting on Saturday (link will take you to calendar) // Events January-February January 1 -The first successful blood transfusion using blood that had been stored and cooled. ...

Several cloverleaves were built in the late 1920s, and it is unclear which was first. Sometimes referred to as the Jazz Age or primarily in North America and in Australia as the Roaring Twenties . In Europe it is sometimes refered to as the Golden Twenties. ...

A modified cloverleaf, with the adjacent ramps joined into a single two-way road, was planned in 1927 for the interchange between Lake Shore Drive (US 41) and Irving Park Road (ILL 19) in Chicago, Illinois, but it is not clear if this was built. 1927 (MCMXXVII) was a common year starting on Saturday (link will take you to calendar). ... Lake Shore Drive is a mostly freeway-standard expressway running parallel with and next to Lake Michigan through Chicago, Illinois, USA. Except for the northernmost part, it is designated as part of U.S. Highway 41. ... United States Highway 41 is a north-south United States Highway that runs from the Upper Peninsula of Michigan to Miami, Florida. ... Chicago, Illinois - Wikipedia, the free encyclopedia /**/ @import /skins-1. ...

The Woodbridge Cloverleaf was built at Route 25 and Route 4 (now US 1/US 9 and Route 35) in Woodbridge Township, New Jersey. It opened in 1929, and is currently planned for replacement with a 5-ramp partial cloverleaf interchange (parclo). This was designed by the Rudolph and Delano building firm from Philadelphia, and was modeled after a plan from Buenos Aires, Argentina. Route 25 was a major state highway in New Jersey, United States prior to the 1953 renumbering, running from the Ben Franklin Bridge in Camden to the Holland Tunnel in Jersey City. ... Route 4 is a state highway in New Jersey, United States. ... United States Highway 1 is a United States highway which parallels the east coast of the United States. ... United States Highway 9 is a north-south United States highway in the states of Delaware, New Jersey, and New York in the United States. ... New Jersey State Highway 35 is a state highway along New Jerseys Atlantic coast. ... Woodbridge Township is a township located in Middlesex County, New Jersey. ... 1929 (MCMXXIX) was a common year starting on Tuesday (link will take you to calendar). ... The parclo interchange (short for partial cloverleaf interchange) is a successor to the cloverleaf interchange. ... Philadelphia is a village located in Jefferson County, New York. ... Buenos Aires (Good Airs in Spanish, originally meaning Fair Winds) is the capital of Argentina and its largest city and port, as well as one of the largest cities in Latin America. ...

The first cloverleaf west of the Mississippi River opened on August 20, 1931 at Watson Road and Lindbergh Boulevard near St. Louis, Missouri as part of an upgrade of US 66.[2] This page is about the river in the United States; there is also a Canadian Mississippi River (Ontario). ... August 20 is the 232nd day of the year (233rd in leap years) in the Gregorian Calendar. ... 1931 (MCMXXXI) is a common year starting on Thursday. ... The Gateway Arch, shown here behind the Old Courthouse, is the most recognizable part of the St. ... U.S. Highway 66 or Route 66 was and is the most famous road in the U.S. Highway system and quite possibly the most famous and storied highway in the world. ...

The cloverleaf was patented in Switzerland on October 15, 1928. The first cloverleaf in Europe opened on November 21, 1936 (but was partly closed until November 5, 1938) at Schkeuditzer Kreuz near Leipzig, Germany. This is now the interchange between the A 9 and A 14, and has a single flyover from the westbound A 14 to the southbound A 9. Kamener Kreuz was the first in continental Europe to open fully in 1937, at A 1 and A 2 near Dortmund Germany. October 15 is the 288th day of the year (289th in Leap years). ... 1928 (MCMXXVIII) was a leap year starting on Sunday (link will take you to calendar). ... Europe - Wikipedia, the free encyclopedia /**/ @import /skins-1. ... November 21 is the 325th day of the year (326th in leap years) in the Gregorian Calendar. ... 1936 (MCMXXXVI) was a leap year starting on Wednesday (link will take you to calendar). ... November 5 is the 309th day of the year (310th in leap years) in the Gregorian Calendar, with 56 days remaining. ... 1938 (MCMXXXVIII) was a common year starting on Saturday (link will take you to calendar). ... Leipzig â–¶(?) [] (Sorbian/Lusatian: Lipsk) is the largest city in the federal state (Bundesland) of Saxony in Germany. ... Overpass in East Potomac Park, Washington, D.C. Flyover in Miami Beach, Florida An overpass (In UK, India, Hong Kong flyover) is a bridge, road or similar structure that crosses over another road. ... Image:Kamener-Kreuz. ... 1937 (MCMXXXVII) was a common year starting on Friday (link will take you to calendar). ... Bundesautobahn 1 (translates from German as Federal Motorway 1, short form Autobahn 1, abbreviated as BAB 1 or A 1) is an Autobahn in Germany. ... Map of the A 2 in Germany The Bundesautobahn 2 (short form Autobahn 2, abbreviated as BAB 2 or A 2) is a freeway in Germany, that connects the Ruhr area in the west to Berlin in the east. ... Map of Germany showing Dortmund Dortmund is a city in Germany, located in the Bundesland of North Rhine-Westphalia, in the Ruhr area. ...

Problems

A point of conflict is the merging of exiting and entering traffic in the same lane, known as weaving. Most road authorities have since been implementing new interchange designs with more straight exit ramps that do not result in weaving. These interchanges include the parclo and SPUI interchanges when connecting to an arterial road, and the stack and cloverstack interchanges when connecting to another freeway. Usually considered in the context of the applied arts, engineering, architecture, and other such creative endeavours, design is used as both a noun and a verb. ... The parclo interchange (short for partial cloverleaf interchange) is a successor to the cloverleaf interchange. ... Spui may refer to the following things: Spui, a river in The Netherlands SPUI (Single Point Urban Interchange), a type of highway interchange This is a disambiguation page — a navigational aid which lists other pages that might otherwise share the same title. ... A stack interchange is a free-flowing junction between two or more roads that allows turning in all directions. ...

A compromise is to add a collector/distributor road next to the freeway; this doesn't eliminate weaving but moves it off the main lanes of the freeway. A collector/distributor road, often abbreviated as C/D road, is a one-way road next to a freeway that is used for some or all of the ramps that would otherwise merge into or split from the main lanes of the freeway. ...

A few cloverleaf interchanges in California have been rebuilt to eliminate weaving on the freeway while keeping all eight loop ramps, by adding bridges. State nickname: The Golden State Official languages English Capital Sacramento Largest city Los Angeles [[List of Governors of {{{Name}}}|Governor]] Arnold Schwarzenegger (R) [[List of United States Senators from {{{Name}}}|Senators]] Dianne Feinstein (D) Barbara Boxer (D) Area  - Total  - % water Ranked 3rd 410,000 km² 4. ...

External links

• An aerial photo of the Woodbridge Cloverleaf