The facility is made from blocks of Quincy granite, quarried across the bay from here. The interior has the block levels staggered to form large steps. Signs on the end nearest the Constitution Museum describe the dry dock and its significance. The web site for the Historic Naval Ships Association has a decription as well. The need for a dry dock facility was recognized as early as 1798. However, it would take many years before the Navy would actually allocate enough money to built one. In 1824, Loammi Baldwin, Jr. a local man who is today considered, "The Father of Civil Engineering," was asked to study and estimate the costs to build a facility in Charlestown. Baldwin's report in November 1824, outlined the design to make the largest ship of the time, the Ship-of-the-Line, U.S.S. Pennsylvania, and the cost to build would be $280,000. The open end would have turning instead of floating gates. The dock would be emptied by a pump with an engine that could power a sawmill when not used by the dry dock. In 1826, Baldwin was also employed to look at other spots, including Gosport Navy Yard. In 1827, Congress authorized money to build two facilities, one at Boston and the other at GNorfolk, VA. At first Baldwin and his brothers supervised the work, but Loammi Baldwin was called to help with building railroads. Baldwin had Alexander Parris, an architect who eventually designed many of the buildings in Washington, DC, take his place. Construction took six years. The dry dock was finished in 1833. On June 24, 1833, thedock took the first customer, the U.S.S. Constitution. According to the web site, "The dock had an overall dimension of 341 x 100 ft. At the dock floor, this dimension was 228 x 30 ft., rising in tiers to 253 x 86 ft. at the top. The chamber between the turning gates and the floating gate was 53 ft. in length, and could be utilized should a vessel's length require it. The floor of the dock was 32 ft. below mean high water, with the top coping 4 ft. above.