Marietta, a city and the capital of Washington co., Ohio, at the confluence of the Ohio and Muskingum rivers, and at the terminus of the Marietta and Cincinnati and the Marietta, Pittsburgh, and Cleveland railroads, 85 m. E. S. E. of Columbus; pop. in 1850, 3,175; in 1860, 4,323; in 1870, 5,218. Including Har-mar, which is part of the town, the population is over 7,000. It is regularly laid out, with wide streets and neatly built houses. On the site of the city there is a remarkable group of ancient works, which are described in Squier and Davis's "Ancient Monuments of the Mississippi Valley" as consisting of "two irregular squares (one containing 40 acres area, the other about 20 acres), in connection with a graded or covered way, and sundry mounds and truncated pyramids. The town of Marietta is laid out over them, and, in the progress of improvement, the walls have been considerably reduced and otherwise much obliterated; yet the outlines of the entire works may still be traced. The walls of the principal square, where they remain undisturbed, are now between 5 and 6 ft. high by 20 or 30 ft. base; those of the smaller enclosure are somewhat less.
The entrances or gateways at the sides of the latter are each covered by a small mound placed interior to the embankment; at the corners the gateways are in line with it. The larger work is destitute of this feature, unless we class as such an interior crescent wall covering the entrance at its southern angle." Marietta has considerable trade in petroleum, which is obtained in the vicinity, and contains several iron founderies, manufactories of buckets, chairs, etc, a union bank, and two national banks. It is the seat of Marietta college, the grounds of which occupy a square, and contain four buildings. This institution was established in 1835, and in 1873-'4 had 11 professors and instructors, 182 students (93 in the collegiate and the rest in the preparatory department), 360 alumni, | and libraries containing 25,000 volumes. The city has flourishing graded schools, including a high school, three weekly newspapers (one German), and 15 churches. Marietta is the oldest town in the state, having been settled in 1788 by New Englanders under Gen. It. Putnam, and named in honor of Marie Antoinette.