Scotland in St. Mary's County, Maryland — The American Northeast (Mid-Atlantic)
The Bay Is a Sunken River
Change on the Chesapeake
The Chesapeake Bay is actually the "sunken" Susquehanna River. After the last ice age, meltwater flooded the river and created the bay, the world's largest estuary. But the bay is tricky for large boats to navigate. Most of it is very shallow; the channel where the Susquehanna once flowed is the bay's only truly deep water. tides and the changing volume or rivers feeding the bay also impact water depth. Meanwhile, wave action and siltation are constantly reshaping the bay floor.
[Captions:]
Depths of the Chesapeake Bay
Mariners check depth by "sounding." They drop a weighted, marked line into the water in a series of spots, then record the data to make constantly updated nautical charts. This dimensional chart shows the various depths, including the "sunken" Susquehanna River channel.
1888 Site Map
As a note on this map indicates, Point Lookout is a "sand spit varying in lengths and shifting in position according to winds and tides." During the 19th century, the Point was tapered toward the southeast.
1999 Site Map
A 1999 site map overlaid with an 1865 map shows a dramatic change over 134 years. The Civil War-era shoreline (yellow line) sat well to the east of the 1999 shore (black).
Erected by Maryland
this page online
Topics. This historical marker is listed in these topic lists: Exploration • Natural Features • Waterways & Vessels. A significant historical year for this entry is 1888.
Location. 38° 2.316′ N, 76° 19.328′ W. Marker is in Scotland, Maryland, in St. Mary's County. It can be reached from Point Lookout Road (Maryland Route 5) 2.3 miles south of 3rd Way, on the right when traveling east. Touch for map. Marker is at or near this postal address: 10344 Point Lookout Rd, Scotland MD 20687, United States of America. Touch for directions.
Regionally, this marker is in Southern Maryland. It is also in the American South, specifically in the Upper South, in the Mid-Atlantic, in the Tidewater, and in the Chesapeake Bay Region. Globally, it is in the North Atlantic Region, North America, the Western Hemisphere, the Western World, and the Anglosphere. Historically, it finds itself in what was once one of the original Thirteen Colonies and also the Antebellum South.
Other nearby markers. At least 8 other markers are within walking distance of this marker: The Wooden Spar Buoy
Additional keywords. cartography
Photographed by Devry Becker Jones (CC0), April 11, 2026
3. Adjacent Stormy Waters sign
Wind, Rain, Hail, & Floods
The Chesapeake Bay usually appears peacefula safe place to travel, swim or cast a line. But many dangers lurk under its waters. From shifting shoals to grass and oyster beds to myriad shipwrecks strewn along the coastlines, mariners who travel carelessly travel at their peril.
Frequent and severe storms can further complicate traveling on the bay. Because of its shallow depth, the Chesapeake is known for its short, steep, choppy waves, which are unpredictable and hard to navigate. These waves have capsized and swamped many vessels.
Credits. This page was last revised on April 14, 2026. It was originally submitted on April 14, 2026, by Devry Becker Jones of Washington, District of Columbia. This page has been viewed 13 times since then. Photos: 1, 2, 3. submitted on April 14, 2026, by Devry Becker Jones of Washington, District of Columbia.
