Numbered highways in the Kingdom of Sierra

Numbered Highway Systems of Sierra
	Highway shields for Interprovincial 1, K.S. Route 91, K.S. Route 101, and Gold Coast Provincial Route 138
System information
Formed:	March 15, 1949
Highway names
Interprovincials:	Interprovincial X (I-X), K.S. Route X

Numbered highways in the Kingdom of Sierra are split into four primary types of systems, the Interprovincial Highways, K.S. Highways, provincial/state/areal highways, and county highways. Other systems include the National Park Highways, Scenic Route Highways, and Reservation Highways. All highways are organized by a route number and/or a letter, often related to its general cardinal orientation (north-south, west-east) and geographic location. These designations are physically displayed through the form of highway shields.

One of the world's largest highway networks, the modern Sierran highway project began in 1949 in response to Sierra's growing demographics and infrastructure. Deemed one of the most ambitious projects in human history, by 1980, nearly 10,000 miles of roads were built or under construction.

The Interprovincial Highway and K.S. Highway Systems are a network of highways that transverse over multiple provinces built to standardized regulations and specifications and is overseen by the federal government. Ultimately, all highways, especially the provincial highways, are the responsibility of the provinces themselves who maintain all roads and highways subject to their jurisdiction. As such, virtually all of the provinces have departments, agencies, and law enforcement bodies dedicated solely for the maintenance, upkeep, and protection of the highway systems.

Interprovincial Highways

The official route marker for Interprovincial highways features a blue shield topped with a red bar that bears the word "INTERPROVINCIAL"

The Interprovincial Highway System was the first national highway system commissioned by the Parliament on March 15, 1949 under the direction of [[Monarchy of Sierra|King Louis III. A network of controlled-access highways, both it and the K.S. Route Highways follow the Sierran Royal Association of Highway and Transportation Officials' standards and regulations. Much of the Interprovincial Highways were constructed prior to 1975 where from that year on, most new national highways became part of the K.S. Route Highway System. Using the same standards, highways from either systems are virtually indistinguishable.

Number	South or west terminus	North or east terminus	Length (mi)	(km)	Formed	Deleted	Became an Interprovincial	Notes
I-1	K.S. SR 16 in Santa Monica, Gold Coast	I-1 at Brazoria-Sierra border	635.3	1,022.42	April 2, 1956	—	April 2, 1956	First Interprovincial formed
I-1A	GC-47 / Gaffey Street in San Pedro, Gold Coast	Glenarm Street in Pasadena, Gold Coast	31.82	51.21	March 3, 1942	—	April 9, 1967	Concurrent with GC-110
I-2	PN Route 1 in Laguna-Pacífico Norte border line at Tijuana	I-5 in Astoria-Sierra border line	796.432	1,281.733	September 19, 1903	—	April 2, 1956
I-2A	K.S. SR 16 near El Segundo, Gold Coast	I-2C in Norwalk	18.82	30.29	July 4, 1971	—	August 5, 1984
I-2B	I-2 in Irvine, Orange	I-2 near San Fernando, Gold Coast	72.415	116.541	May 13, 1967	—	August 5, 1984
I-2C	K.S. 22/I-2B in Seal Beach, Orange	File:Route 41 (Gold Coast).svg GC 41 / Huntington Dr in Irwindale, Gold Coast	27.40	44.10	July 9, 1941	—	August 5, 1984
I-3	I-2 in San Diego, Laguna	DR 2 in Mohave-Deseret border at St. George	446.846	719.128	August 13, 1947	—	April 2, 1956
I-3A	I-3 in Murrieta, Inland Empire	I-3 in San Bernardino, Inland Empire	55.060	88.610	April 9, 1963	—	September 5, 1982