Category:Infrastructure completed in 1721 Architecture portalEngineering portalThis category is for infrastructure completed in the year 1721.17151716171717191720172117221723172417251726 1670s1680s1690s1700s1710s1720s1730s1740s1750s1760s1770s Subcategories This category has only the following subcategory. T Transport infrastructure completed in 1721 (1 C)
