View Question
 Question
 Subject: Length of US Coastline Category: Reference, Education and News > General Reference Asked by: junglejane-ga List Price: \$4.00 Posted: 10 Apr 2002 11:26 PDT Expires: 17 Apr 2002 11:26 PDT Question ID: 33
 ```What is the length of the perimeter of mainland United States and that of Alaska and Hawaii?```
 Subject: Re: Length of US Coastline Answered By: dscotton-ga on 10 Apr 2002 12:04 PDT Rated:
 ```The CIA World Factbook lists the land boundaries of the United States as 12,248 kilometers (7612 miles), and the coastline as 19,924 km (12,383 miles). These numbers include all US territory. The Factbook doesn't break these numbers down except to say that 2,477 km (1539 miles) of the land boundary consists of Alaska's border with Canada, and that 29 km (18 miles) consists of the border between Cuba and the US Naval Base at Guantanamo Bay. The rest of the land boundary is presumably part of the perimeter of the contiguous 48 states. http://www.cia.gov/cia/publications/factbook/geos/us.html The Learning Network has a breakdown of coastline length by state. According to their web page, Hawaii has 750 miles of coastline (which should be the sum of the perimeter of each of its islands). Alaska has 5,580 miles of coastline. That would make the total perimeter of Alaska 7,119 miles (5580 miles of coast + 1539 miles of land boundary). Subtracting Alaska and Hawaii, the contiguous 48 states have 6053 miles of coastline and 6055 miles of land boundaries, for a perimeter of 12108 miles. http://www.infoplease.com/ipa/A0001801.html```
 junglejane-ga rated this answer: `Just the numbers I was looking for!`

 ```Using concepts from fractal geometry, mathematicians make the argument that the US coastline is of infinite length. Imagine two poles separated by 50 meters of rope. If two men grab these poles, stretch out the line between them, and "walk off" the distance around a lake, they might find that it required 20 lengths of this rope to circumnavigate the lake. Thus, they would calculate that the lake has 50 x 20 = 1000 meters of shore. Now, if the length of the line is reduced to 20 meters, the men would be able to map the shore more accurately, as fewer rocky outcroppings would be skipped in the measuring process. Using this shorter rope, the men might require 70 lengths to go around the lake. Thus, they would calculate the coast to be 20 x 70 = 1400 meters in length. Now, if the rope were 10 cm in length, the men would catch the individual rocks that make up the coast, but they would miss the pebbles. If the rope were 1 cm in length, they would catch the individual rocks, but they would miss the pebbles. If the rope were 1 mm in length, they would catch the pebbles, but they would miss the grooves in the edges of the pebbles.... and so on down to subatomic particles. In short, the closer you trace the coastline, the longer it gets. Some sources: http://www.bbc.co.uk/dna/h2g2/alabaster/A425972 http://www.msri.org/activities/jir/bwachtel/MeasuringtheCoast.html http://www.calresco.org/fractal.htm http://www.earthsky.com/2000/es001104.html Google search: ://www.google.com/search?q=fractal+%22infinite%22+coastline```
 ```It appears that the answer above contains an error. According to the source referred to (http://www.infoplease.com/ipa/A0001801.html) the coastline of Alaska is 6640 miles not 5580. This is the total of Alaska's Pacific coast (5580) and its Arctic coast (1060). The answer omitted the Arctic coast and the totals are off by this amount.```