In 1700, the population of the British North American colonies was concentrated mainly along the coast. Roads were terrible and dangerous, and most people would have used the natural highways, the rivers and estuaries that came in from the coast . The estuaries were navigable all the way to the Fall Line, which allowed navigation well into the interior. For these trips, smaller vessels and possibly even rafts were used.
However, towards the end of the 17th century, some roads began to develop. The most important of these were the Post Roads. After the Restoration, Charles II decreed that such roads be made, and a system sometimes called the "King's Highway" stretched from Boston down to Charleston by the 1750's. (Interactive map at the Library of Congress). However, these "roads" were initially just trails already established by Native Americans, and their improvement into roads was a piecemeal affair constructed by the various colonies.
The "Boston Post Road" connected New York with Boston. This article about the post road in Connecticut says
A royal charter in 1691 revitalized postal service throughout the English colonies in North America along a route that extended from Baltimore to Portsmouth, Maine.
("Baltimore" per se didn't exist in 1691; the old Baltimore on the Bush River was mostly dead by this time, replaced by Joppa, and the current one was only founded in 1729. And it's not clear if they mean Portland, Maine or Portsmouth, New Hampshire).
This 1729 map by Herman Moll shows the road from Boston to Philadelphia:
Source: Wikimedia Commons, resized by me
The section in Maryland was established in 1666. Most colonial maps of Maryland show no roads at all: Everyone used the Chesapeake Bay. Here's a link to an interactive map at the Library of Congress showing the roads in Maryland and Virginia from 1751, and here's a detail of the road in Maryland:
The Post Road goes from a ferry at "Charles Town" (now Port Tobacco) up to Philadelphia. Note that the "Baltimore" shown is the old one. The "Great Wagon Road" began appearing in the 1750s.
NCPedia.org says this about post roads in the Carolinas:
Until 1792 post roads through North Carolina, such as they were, served only a few coastal towns; anyone who lived in the interior had to depend on travelers or private mail carriers to carry their letters to and from the coastal post offices.