Hotel Indigo Excavation Update: The Early Shoreline and More Recent Finds

Throughout October, code-required excavations continued prior to the construction of the Indigo Hotel. Archaeologists peeled back the layers of time. The entries and photos below will reveal their discoveries.

Page archived as of March 11, 2019

Note: The information on this page reflects the state of knowledge when this update was written. Information may have changed. 

The Early Shoreline and More Recent Finds

October 2015

Throughout October, consultants from Thunderbird Archaeology (a division of Wetland Studies, Inc.) continued their code-required excavations at 220 S. Union Street prior to the construction of the Indigo Hotel. They peeled back the layers of time and found themselves mired in the sands of the mid-18th century, about 4 to 6 feet below the current ground surface (in the area being excavated for the hotel garage). The entries and photos below will take you back through time to reveal their discoveries of evidence of Alexandria’s earliest history, including the shoreline of the town’s original cove. 

Recording the Site

One of the most important parts of doing archaeology is recording the things we find. The story of the past comes from understanding the context of archaeological discoveries—not just from the discoveries themselves. Archaeologists locate artifacts and features both horizontally across the landscape and vertically as they dig down into the soil layers, getting earlier and earlier with depth. The dates of the artifacts from each layer help to determine the time period of occupation, and analysis of the types of artifacts sheds light on the activities that occurred across the site during a particular era.  Archaeological features associated with the periods of occupation include obvious human additions to the landscape, such as foundations or wells, or other more subtle evidence of human disturbance to the soil, recognized as differences in soil color and texture within the stratigraphic layers.

In this photo, archaeologists are using surveying equipment to record the locations of archaeological features, marked here by pin-flags. This equipment is frequently used to measure and record features and sites with extremely high accuracy.  The resulting data will be mapped and published with the report from this site.


The 1749 Shoreline 

Also, note the two very distinct types of soil present in the above photograph.  On the right is lighter-colored sandy soil and on the left is darker-colored clayey soil.  According to our research with period maps, the city’s original, circa-1749 shoreline runs through the lot at approximately this location.  If this soil change represents the historic shoreline, then all of the ground to the east—between here and the river—is imported fill that has been deposited as the city grew.   


Prior to demolition at 220 S. Union Street, the block’s sidewalk along Duke Street was made from concrete and built low to the street so that trucks could back up right to the warehouse and unload into one of four loading docks. Under this concrete sidewalk, archaeologists have discovered an earlier brick sidewalk.  Note the diagonal brick pattern, which is characteristic of some blocks in Old Town today, but unlike the existing brick sidewalks now seen in the immediate area of the site.  

220 S. Union Street: Sidewalk

Iron box

This riveted iron box was encountered near the west side of the lot, close to S. Union Street. Inside were accumulated soils and architectural debris. The size and weight of this box required special equipment to remove it. Current interpretations indicate that this box was either associated with the Bryant Fertilizer Company or a later structure, built in 1959 and demolished just recently to make way for the present construction of the Indigo Hotel.

220 S Union Iron Box

A Revised Interpretation

As archaeologists dig any site, they are constantly asking questions about the date and function of their discoveries. On historical sites, they continually go back to their documentary information to try to integrate the historical and archaeological records. The interpretation of the use of the brick floor area featured in the September update has changed since its posting. Thunderbird archaeologists report that the feature was most likely associated with the Bryant Fertilizer use of the property, but it exact function is unknown at this time. The small hole was attributed to earlier geotechnical boring.   


The archaeologists on site have identified many postholes. This photograph shows the remains of a wooden post.  Archaeologically, posts are distinctive features, frequently consisting of two parts. The larger, outside circle is called a posthole and is the result of digging a hole in the ground, placing a wooden post into this hole, and filling in the remainder of the hole around the post with dirt. The smaller, darker feature in the center of the post hole is called a post mold and is usually the result of the wooden post decaying in the ground. Here at 220 S. Union Street, the wooden post has not decayed and you can still see part of it above the ground surface. Ordinarily, wood like this does not survive in the ground for very long; however, the wetness of the soil and the fact that many of these posts may have burned have probably contributed to their survival.

220 S Union Post hole 1

When archaeologists find a row of postholes, like the one seen here, it is strong evidence for a fence line, building, or, given the proximity to the river and fill soils, perhaps a pier or wharf. Thunderbird archaeologists are interpreting these posts as the support for a building or a fence that lined an alley that once cut through the lot. They have excavated to the bottom of the post holes, and they are less than 2 feet deep--not deep enough to have been pilings for pier supports.  

220 S Union Post hole 2

Stone Wall

This stone wall was found along the north side of the lot, up against the neighboring building to the north of 220 S. Union Street. It is probably the foundation for a warehouse that was constructed on this northern adjoining lot in the late 18th and early 19th-century. The use of stone (often a type of rock known as schist) for foundations in Alexandria generally predates 1830, when fired bricks became strong enough to be used for this purpose.  

220 S Union Stone Wall

Running under many of the beams of the warehouse is a stone foundation wall.  In some places, this wall is more than three feet deep and helps to support the weight of the massive building above it.  


A pair of privies was discovered on the site. These are located next to each other in the back corners of two adjacent parcels on the lot, which is where privies were frequently located. Tax records show there were structures on these two parcels—the first at the corner of S. Union Street and Duke Street and the second just north of that along S. Union Street—by 1802. Because we can learn a lot from privies, especially about the kinds of things people were eating, much of the soil from these contexts will be screened through much smaller mesh (1/16” instead of the usual 1/4”) to recover smaller objects that would ordinarily fall through our screens. An analysis of the ceramics and other artifacts recovered from these privies can also help us determine when these privies were in use as well as other important information about the people living and working on this site.

220 S Union Privy


This piece of coral was found under the Strand and is indigenous to the Caribbean. Coral was sometimes used as ballast to keep ships balanced and floating at the appropriate height in the water.  When taking on cargo, this ballast is no longer needed and dumped. It is frequently said that many old cobblestone streets are constructed from dumped ballast.  This piece of coral was also found with cobbles and timbers, suggesting it was most likely former ballast dumped and incorporated into new land fill behind a retaining wall or next to a pier or wharf.  It serves as a reminder of the “triangular trade” between Great Britain, the colonies of British North America, and British colonies in the Caribbean. 

220 S Union Coral

Thunderbird Archaeologist John Mullen holds up a piece of coral recovered from under The Strand. It was probably brought here as ballast and unloaded at the waterfront.