According to ehuacom.com, Charleston is the largest city in the US state of South Carolina, located on the Atlantic Ocean. Charleston has a population of 152,000 and an urban agglomeration of 813,000 inhabitants (2021).
According to mcat-test-centers, Charleston is located in the lowlands of the Atlantic Ocean, at the confluence of several tidal rivers in the Charleston Harbor. Historic downtown Charleston is about 5 miles from the open sea. The city is largely located on a peninsula between the Cooper River and the Ashley River. Other rivers include the Wando River and Stono River. The rivers are wide and mainly flow through tides. The environment of these rivers consists mostly of wetlands. As a result, the urban area of Charleston has become very fragmented and has grown far inland. The suburbs extend up to 50 kilometers inland. Several islands around Charleston and on the coast are also suburbanized.
Charleston’s economy is diverse. It is one of the larger ports on the US East Coast, with container ports on the Cooper River and Wando River. There is also the large Charleston Naval Shipyard of the US Navy. The United States Air Force is also represented at Charleston Air Force Base. The city is also a tourist destination, it is one of the oldest cities in the United States and has long sandy beaches on the Atlantic Ocean. Also famous is Fort Sumter, where the American Civil War started. Charleston’s economy has grown strongly since 2000, with very high population growth for a city of this size. Charleston is in transition from a regional city to one of the major cities of the southeastern United States.
The metropolitan area of Charleston extends over three counties; Charleston County (significantly larger than the city itself), Berkeley County and Dorchester County.
US 17 at Charleston.
Charleston is located on a peninsula, so most traffic is concentrated north-south. Interstate 26 is the primary connection for this traffic, almost all regional traffic ends up on I-26 at some point. I-26 has partial 2×4 lanes. The Charleston bypass is formed by Interstate 526, this highway has 3 major bridges and connects the suburbs and inner suburbs of Charleston. In North Charleston, I-26 and I-526 intersect, this is the only true interchange of the Charleston region. I-26 and I-526 are also Charleston’s only true freeways.
The underlying road network is formed by urban arterials. The US 17 is the most important of these. US 17 has two separate bridges on the west side of downtown and goes through the large Arthur Ravenel Jr. Bridge over the Cooper River. This bridge is the most iconic in the southeastern United States. The bridge itself has 2×4 lanes but splits east of the Cooper River into two urban arterials. US 17 also has an alternate 199-kilometer route that bypasses the entire Charleston region, but this is not a high-quality connection.
US 78 forms a secondary connection next to I-26. The US 52 is the main connection to the north, this is a 2×2 divided highway that connects the northern suburbs of Charleston. US 176 and US 178 are secondary roads that coincide with US 52 and US 78 in Charleston.
There are also a number of bridges on which traffic to and from the islands and between the rivers depends. However, the rivers have relatively few crossings, so that traffic is concentrated on a limited number of connections and the detour distance is relatively large. The most well-developed route of these is State Route 30, also known as the James Island Expressway.
The Charleston area has no toll roads or express lanes.
The Arthur Ravenel Jr. Bridge of US 17.
Freeways in Charleston
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Charleston is a low-lying city on the Atlantic Ocean and therefore vulnerable to hurricanes. The problems for Charleston are then multifold, in addition to the strong wind, especially the storm surge and rainfall. In addition, the region is densely forested so that strong winds quickly cause power failures, which can be long-lasting. To evacuate Charleston in the event of an approaching hurricane, the entire I-26 as far as Columbia can be deployed in counterflow. All lanes will then be out of town to just before I-77 in Columbia.
In 1999, Hurricane Floyd threatened the South Carolina coast, and it was decided to evacuate the Charleston region. There was no proper counterflow script at the time, causing a traffic chaos, with the drive from Charleston to Columbia taking 14-18 hours, while normally it’s barely 2 hours. In 2016, counterflow was first deployed due to the approaching Hurricane Matthew. In 2018, counterflow was used due to the approach of Hurricane Florence  and in 2019 due to the approaching Hurricane Dorian. 
I-26 at Charleston.
Charleston is one of the oldest cities in the United States, and the first in the English-speaking part to be built to a master plan in the 18th century. The town was then known as Charles Town, named after Charles II of England. From the beginning, the city was seen as a potential port city. From 1719 the name of the city was written as Charlestown and from 1783 the name was formally Charleston. The American Civil War broke out in Charleston on April 12, 1861. The first shots were fired from Fort Sumter. The city was destroyed, rebuilt and nearly destroyed again in 1886 in an earthquake.
In the early 20th century, more infrastructure began to be built in Charleston. One problem for the city was that it was surrounded by tidal rivers. In 1929, the John P. Grace Memorial Bridge opened over the Cooper River, connecting the city to the coastal region to the east. In 1966 a second bridge opened next door to increase capacity, these bridges were replaced in 2005 by the Arthur Ravenel Jr. Bridge, a large cable-stayed bridge.
Charleston’s primary highway (I-26) was constructed at a time when the metropolitan region consisted primarily of the city of Charleston and the region had a population of some 200,000. I-26 opened in the 1960s and ended north of downtown to join what was then the bridge over the Cooper River. In the 1980s, Interstate 526 constructed as a bypass of Charleston, this was realized just after a period of rapid growth of the region, during which new suburbs such as Goose Creek, Sangaree and Summerville developed. I-526 was completed in 1992. During this period, I-26 was also widened to 2×3 lanes. Later in the 1990s, the 2×3 section was extended further north to Summerville. Due to the enormous population growth after 2000, I-26 was widened again in 2010-2012, to 2×4 lanes in the northern suburbs, followed by another widening further north in 2018. The James Island Expressway was built in the early 1990s as an improved access route between the downtown and James Island in southwest Charleston. The lack of river crossings, alternative routes and limited motorway network are increasingly affecting the region.
The highest traffic volume in Charleston in 2017 was I-26 with up to 191,000 vehicles per day.
Congestion in Charleston became notorious after 2000. In 2016, Charleston appeared for the first time in TomTom’s Travel Time Index, ranking 15th in the United States and the smallest place with such a high ranking. The cause of the severe congestion in relation to the population is the incomplete road network, due to its location in a region with bays, tidal rivers and swamps, there are few connections and at some point a lot of traffic ends up on I-26.