The ICW

The Intracoastal Waterway - c.3,000 mi (4,827 km) long, partly natural, partly artificial, providing sheltered passage for commercial and leisure boats along the U.S. Atlantic coast from Boston, Mass. to Key West, S Fla., and along the Gulf of Mexico coast from Apalachee Bay, NW Fla., to Brownsville, Tex.,on the Rio Grande.
The Intracoastal Waterway or ICW was first authorized in 1919 and it is maintained by the Army Corp of Engineers. 
Each state is to maintain their buoys, lights and other navigational markers but the Army Corp does the dredging in the ICW
to keep the water depth at 10-12 ft. This allows for safe passage for most commercial and recreational vessels.
The new bridges are 65ft tall and this height allows most vessels to go under them without any problem.  

Among some of the waterway's most often used canals along the Atlantic route are the Chesapeake & Delaware and the Chesapeake & Albemarle;
along the Gulf route the most used are the New Orleans–Rigolets Cut, the Port Arthur–Corpus Christi Channel,
and the Inner Harbor Navigational Canal at New Orleans. The separate Okeechobee Waterway, S Fla., crosses the Florida peninsula.
Plans to build a canal across N Florida to link the Atlantic and Gulf sections were blocked in 1971
by a presidential order to prevent potential environmental damage. Many miles of navigable waterways connect with the coastal system,
including the Hudson River–New York State Canal System, the Chesapeake Bay, the sounds of North Carolina,
the Savannah River, the Apalachicola River, and the entire Mississippi River system.
The Intracoastal Waterway has a good deal of commercial activity; barges haul petroleum, petroleum products, foodstuffs,
building materials, and manufactured goods.

As you can see, traveling the ICW requires working knowledge of the rules... Here are some helpful links
Boat-ed.com
Learn the meaning of the markers along the ICW
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National Vessel Documentation Center--
Download all the forms and instructions to do it yourself.
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CoastalSailing.net
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Ship's Radio License Application form -
( for most yachts and pleasure boats,
only needed if you will be cruising to Mexico, the Bahamas,
or beyond or if you will be using a marine SSB radio )
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