Milltown High Street Bridge (Warren County, Pennsylvania)
Built 1937; rehabilitated 1982
Pony truss bridge over Tionesta Creek on PA 2002 (High Street) in Milltown
Open to traffic

Milwaukee River Parkway, Lincoln Park, North Branch (Milwaukee County, Wisconsin)
Built 1940
Bridge over North Branch Milwaukee River on Milwaukee River Parkway
Open to traffic

Milwaukee River Parkway, Lincoln Park, South Branch (Milwaukee County, Wisconsin)
Built 1940
Bridge over South Branch Milwaukee River on Milwaukee River Parkway
Open to traffic

Mine Creek Bridge (Linn County, Kansas)
Built 1914
Concrete arch bridge over Mine Creek, 8.8 mi. north and 3.4 mi. east of Prescott
Open to traffic

Mine Creek Bridge (Linn County, Kansas)
Built 1927
Rainbow arch bridge over Mine Creek on Ungeheuer Road (Old US 69), five miles north of Prescott
Open to traffic

Miner Street Bridge (Clear Creek County, Colorado)
Built 1902 by Kuyes and Work. Reconstructed 1990 (the trusses are no longer load-bearing).
Reconstructed pony truss bridge over Clear Creek on Miner Street in Idaho Springs
Open to traffic

Minerva Creek Bridge (Marshall County, Iowa)
Built 1919
Pony truss bridge over Minerva Creek on a local road
Open to traffic

Minerva Creek Bridge (Marshall County, Iowa)
Built 1912
Arch bridge over Minerva Creek on a local road
Open to traffic

Mingo Ditch Bridge (Stoddard County, Missouri)
Formerly a bridge on the Frisco Hoxie Branch railroad built in 1926 (?) and refurbished for vehicle use when the line was discontinued
Pony truss bridge over Mingo Ditch southwest of Puxico on CR 499
Open to one-lane traffic on a gravel road with a 17 ton weight limit

Mingo Ditch Route T Bridge (Stoddard County, Missouri)
Built 1955
Steel stringer bridge with wooden piers over Mingo Ditch on Route T
Open to two-lane traffic

Minneapolis Railroad Bridge (Ottawa County, Kansas)
Through truss bridge over Pipe Creek on the Kyle Railroad at Minneapolis
Open to traffic

Minnesota River Bridge (Blue Earth County, Minnesota)
Built 1954
Through truss bridge over Minnesota River on CR 42
Open to traffic

Minot Viaduct (Ward County, North Dakota)
Massive steel railroad trestle over the Coteau di Missouri Valley on the BNSF Railroad, west of Minot
Still in use

Mississippi County Road 307 Bridge (Mississippi County, Missouri)
Built 1921
Pony truss on CR 307 (Old US 60) near Birds Point over a drainage ditch emptying into Brewer Lake in Wyatt
Open to traffic on a paved road with a 20 ton weight limit

Mississippi County Road 310 Bridge (Mississippi County, Missouri)
Built ca. 1922; relocated here 1966
Pony truss bridge over a drainage ditch on CR 310
Open to traffic

Mississippi County Road 314 Bridge (Mississippi County, Missouri)
Built 1922 as part of a bridge with at least two spans; relocated here in 1965
Pony truss bridge over Ditch 29 on CR 314, just off MO 77 south of Wyatt
Open to traffic

Mississippi County Road 319 Bridge (Mississippi County, Missouri)
Built 1922 as part of a bridge with at least two spans; relocated here 1965
Pony truss bridge over Ditch 29 on CR 319 just off MO 77
Open to traffic

Mississippi County Road 322 Bridge (Mississippi County, Missouri)
Built ca. 1922; relocated here 1966
Pony truss bridge over Spillway Ditch on CR 322 southeast of Charleston
Open to traffic on a gravel road

Mississippi County Road 325 Bridge (Mississippi County, Missouri)
Built 1922; relocated here in 1966
Pony truss bridge over Spillway Ditch on CR 325 southeast of Charleston
Open to traffic on a gravel road

Mississippi County Road 418 Bridge (Mississippi County, Missouri)
Built ca. 1922; relocated here 1970
Pony truss bridge over St. James Ditch on CR 418 west of MO 105
Open to traffic

Mississippi County Road 521 Bridge (Mississippi County, Missouri)
Built ca. 1922; relocated here 1965
Pony truss bridge on CR 521 over Wilkinson Drainage Ditch just west of MO 102
Open to traffic

Mississippi River Bridge (Grant County, Wisconsin)
Built 1982
Steel through arch bridge over Mississippi River on US 61/US 151
Open to traffic

Mississippi River I-40 Bridge (Shelby County, Tennessee)
Built 1973
Two-span steel through arch bridge over the Mississippi River on I-40 at Memphis
Open to traffic

Mississippi River US 61 Bridge (Dubuque County, Iowa)
Built 1982
Steel through arch bridge over the Mississippi River on US 61 and US 151
Open to traffic

Missouri Street Bridge (Washington County, Missouri)
Pony truss bridge over Breton Creek on Missouri Street in Potosi, just south of the courthouse
Open to traffic

Mobridge Railroad Bridge (Walworth County, South Dakota)
Through truss bridge over Missouri River (Oahe Lake) on the BNSF Railroad between Mobridge and Wakpala
Open to traffic

Moline Main Street Bridge (Elk County, Kansas)
Pony truss on North Main Street over Wildcat Creek in Moline
Open to one lane traffic on a paved street

Mollys Run Bridge (Jefferson County, Indiana)
Built 1905
Pony truss bridge over Mollys Run on Brooksburg Manville Road (CR 260N)
Open to one-lane traffic

Monett Business US 60 Bridge (Barry County, Missouri)
Built 1935
Through truss bridge over the railroad on Business US 60 east of Monett
Open to two-lane traffic

Moniteau Creek Road Bridge (Cole County, Missouri)
Built 1915; made obsolete by a new bridge on MO 179 in 1967
Through truss bridge over Moniteau Creek on Moniteau Creek Road (Old MO 179)
Open to traffic

Montezuma Bridge (Parke County, Indiana)
Built 1949; rehabilitated 1987
Six-span through truss bridge over Wabash River on US 36 at Montezuma
Open to two-lane traffic

Montoursville Bridge (Lycoming County, Pennsylvania)
Built 1931; rehabilitated 1994
Three-span through truss bridge over Loyalsock Creek on PA 2014 in Montoursville
Open to traffic

Monument Road Bridge (Harris County, Georgia)
Built 1930
Truss bridge over Sand Creek on Monument Road
Open to traffic

Morgan Oak Street Arch Bridge (Cape Girardeau County, Missouri)
Small concrete arch bridge on Morgan Oak Street over a ditch formerly occupied by the Missouri Pacific Railroad
Open to traffic on a city street

Morrison Bluff Bridge (Logan County, Arkansas)
At 1.6 miles this is the longest bridge in Arkansas
Bridge over Arkansas River on AR 109 at Morrison Bluff
Open to traffic

Morton Bridge (Ray County, Missouri)
Built by the Wrought Iron Bridge Co.
Through truss bridge over Crooked River on Landing Road
Open to traffic

Mosby Creek Covered Bridge (Lane County, Oregon)
Built in 1920. Oldest covered bridge in Lane County. Restored in 1990.
Howe through truss bridge on Mosby Creek Road
Open to traffic

Moscow Covered Bridge (Rush County, Indiana)
Built 1886 by E. L. Kennedy
Two-span covered bridge over Flatrock River on CR 900S at Moscow
Open to one-lane traffic

Mossy Creek Route 613 Bridge (Augusta County, Virginia)
Built 1910
Pony truss bridge over Mossy Creek on Route 613
Open to traffic

Mound Road Bridge (Shelby County, Indiana)
Through truss bridge over Flatrock River on Mound Road
Open to traffic

Moundsville WV 2 Spur Over Ohio River (Marshall County, West Virginia)
Built 1986
Steel through arch bridge over Thmpsn Av;Lckwd Av;Ohior on Wv 2 Spur
Open to traffic

Mount Carmel Bridge (Wabash County, Illinois)
Built 1932; rehabilitated 1987
Through truss bridge over Wabash River on IL 15/IN 64 in Mount Carmel
Open to traffic

Mount Hope Bridge (Bristol County, Rhode Island)
Built 1929; rehabilitated 1985
Suspension bridge over Mount Hope Bay on RI 114 in Bristol
Open to traffic

Mount Pleasant Covered Bridge (Perry County, Pennsylvania)
Built 1918
Covered bridge over Shermans Creek on Mount Pleasant Road (TR 304)
Open to traffic

Mountain Fork Bridge (Polk County, Arkansas)
Built 1905
Two-span pony truss bridge over Mountain Fork Creek on CR 38 near the community of Camp Pioneer
Open to traffic

Mountain Fork River Bridge (McCurtain County, Oklahoma)
Built 1948
Through truss bridge over Mountain Fork River on US 70
Open to traffic

Mountain Glen Bridge (Union County, Illinois)
Pony truss bridge over a branch of Clear Creek near Mountain Glen
Open to traffic on a paved road

Mud Creek Bridge (Marion County, Kansas)
Concrete pony arch bridge over Mud Creek, 0.6 mi. north of Marion
Open to traffic

Muddy Creek Old US 65 Bridge (Pettis County, Missouri)
Built ca. 1930
Through truss bridge over Muddy Creek on Claycomb Road (Old US 65) north of Sedalia
Open to traffic

Mulberry Relief Creek Bridge (Franklin County, Arkansas)
Built 1940
Steel stringer bridge over Mulberry Relief Creek on CR 67 - D
Open to traffic

Mulberry River AR 23 Bridge (Franklin County, Arkansas)
Built 1935 by McEachin and McEachin, Inc., of Little Rock
Three-span pony truss bridge over Mulberry River on AR 23
Open to traffic

Mulberry River US 64 Bridge (Crawford County, Arkansas)
Built 1929; rehabilitated 1961
Three-span open-spandrel arch bridge over Big Mulberry River on US 64 in Mulberry
Open to traffic

Mulladay Hollow Bridge (Carroll County, Arkansas)
Built ca. 1935 by the Civilian Conservation Corps
Small two-span stone arch bridge over Mulladay Hollow Creek on CR 204 at Leatherwood Lake Recreation Area northwest of Eureka Springs in Eureka Springs
Open to traffic

Mullen Covered Bridge (Ashtabula County, Ohio)
Built 1876; rehabilitated 1987-88
Covered bridge over Mill Creek on Doyle Road
Open to traffic

Murphy Drive Bridge (Caldwell County, Missouri)
Built ca. 1930
Pony truss bridge over Long Creek on S.W. Murphy Drive
Open to traffic

Murray Baker Bridge (Peoria County, Illinois)
Built 1958; rehabilitated 1984 and 2005
Cantilevered through truss bridge over Illinois River on I-74 in Peoria
Open to traffic

Muscatatuck River IN 256 Bridge (Washington County, Indiana)
Built 1941; rehabilitated 1982
Through truss bridge over Muscatatuck River on IN 256
Open to traffic

Muscatatuck River IN 256 Bridge #2 (Jackson County, Indiana)
Built 1941
Parker through truss bridge over Muscatatuck River on IN 256
Open to traffic

Myers Creek Bridge (Forrest County, Mississippi)
Built 1934
Steel stringer bridge over Myers Creek on US 49 (Northbound Traffic)
Open to traffic

N. 45th Street Bridge (Milwaukee County, Wisconsin)
Built 1952
Pony plate girder bridge over Menomonee River on N 45th Street in Milwaukee
Open to traffic

N. East Street Bridge (Faribault County, Minnesota)
Built 2002 Previous span consisted of a Howe pony truss bridge built in 1910. Bridge was abandond for years and was subject to a huge debate beginning in 1998.
Stringer bridge over E Fork Blue Earth River on City St # 88 at 1st Street
Open to traffic

N. Main Street Bridge (Los Angeles County, California)
Built 1910
Concrete arch bridge over Los Angeles River on N Main Street in Los Angeles
Open to traffic

N. Sunny Point Road Bridge (Milwaukee County, Wisconsin)
Built 1928
Deck truss bridge over N. Sunny Point Road on CNW RR in Glendale
Open to traffic

Nahma Bridge (Delta County, Michigan)
Built 1917 by the Joliet Bridge & Iron Co.; closed to traffic in 1995; relocated Summer 2006
Pony truss bridge formerly over Sturgeon River on CR 497
Relocated to a golf course

Narrow Bridge (Bedford County, Pennsylvania)
Built 1935 by the Pittsburg Construction Co.
Open-spandrel arch bridge over Raystown Branch of Juniata River on US 30
Open to traffic

Narrows Bridge (Cleburne County, Arkansas)
Built 1961 in conjunction with the creation of the lake
Continuous through truss bridge over Little Red River (Greers Ferry Lake) on AR 16 between Higden and Greers Ferry
Open to traffic

National Avenue Bridge (Bourbon County, Kansas)
Built 1933; rehabilitated 1983
Marsh arch bridge over Marmaton River on National Avenue (Old US 69) in Fort Scott
Open to traffic

Natural Dam Bridge (Crawford County, Arkansas)
Built 1934 by contractor M.E. Gillioz, replacing an earlier truss bridge built in 1907 by the Illinois Steel Bridge Co.
Two-span through truss bridge over Lee Creek on AR 59 near the community of Natural Dam
Open to traffic

Neff's Mill Covered Bridge (Lancaster County, Pennsylvania)
Built 1875
Covered bridge over Pequea Creek on Penn Grant Road
Open to traffic

Neosho River Bridge (Lyon County, Kansas)
Built ca. 1940
Through truss bridge over Neosho River, 0.5 mi. west of Neosho Rapids
Open to traffic

Neosho River Bridge (Coffey County, Kansas)
Built 1926
Two-span Marsh arch bridge over Neosho River on 19th Road, 0.2 mi. east of Hartford
Open to traffic

Neosho River Bridge (Neosho County, Kansas)
Through truss bridge over Neosho River on 42.5-17.6 Local, 1.0 mi. east and 2.6 mi. south of St. Paul
Open to traffic

Neosho River Bridge (Neosho County, Kansas)
Built 1928
Through truss bridge over Neosho River, 1.2 mi. south and 0.4 mi. west of Erie
Open to traffic

Neosho River Bridge (Lyon County, Kansas)
Parker through truss bridge over Neosho River on Atchison, Topeka, and Santa Fe (ATSF) Railroad
Open to traffic

Neosho River Bridge (Neosho County, Kansas)
Built 1954
Through truss bridge over Neosho River, 0.4 mi. west of Shaw
Open to traffic

Neosho River K-58 Bridge (Neosho County, Kansas)
Built 1937
Through truss bridge over Neosho River on K-58
Open to traffic

Nevins Covered Bridge (Parke County, Indiana)
Built 1920 by J.A. Britton
Covered bridge over Little Raccoon Creek on CR S130E
Open to traffic

New Bluff Hall Bridge (Adams County, Illinois)
Built 1941
Tee beam bridge over Harkness Creek on IL 57 at Bluff Hall
Open to two-lane traffic

New Canal Bridge (Madison County, Illinois)
Built ca. 1963
Pair of cantilevered through truss bridges over Chain of Rocks Canal on I-270 in Granite City
Open to traffic

New Germantown Covered Bridge (Perry County, Pennsylvania)
Built 1891
Covered bridge over Shermans Creek on TR 302
Open to traffic

New Lick Log Creek Bridge (Bollinger County, Missouri)
Originally built ca. 1922 on a state highway. Relocated here in 1995 to replace the older Lick Log Creek Bridge (now derelict)
Refurbished pony truss bridge over Lick Log Creek on CR 736 near Gipsy
Open to traffic with no posted restrictions

New Madrid County Road 626 Bridge (New Madrid County, Missouri)
Built 1954; rehabilitated 1986
Wooden deck bridge over Otter Slough Ditch on CR 626 southwest of Matthews
Open to one-lane traffic with a 13 ton weight limit

New Madrid County Road 630 Bridge (New Madrid County, Missouri)
Built 1966; rehabilitated 1995
Wooden deck bridge over Ash Slough Ditch on CR 630 at Route AE
Open to one-lane traffic

New Portland Wire Bridge (Somerset County, Maine)
Built ca. 1866; rehabilitated 1961
Suspension bridge over Carrabasset River on Wire Bridge Road in New Portland
Open to traffic

New River Gorge Bridge (Fayette County, West Virginia)
Opened Oct. 22, 1977
Massive steel arch bridge over New River on US 19
Open to traffic

New Rothrock Mill Bridge (Crawford County, Indiana)
Built 2005; replaced the old Rothrock Mill Bridge
Warren pony truss bridge over Blue River on Rothrock Mill Road (Co. Rd 120 South)
Open to traffic

New Steelbridge Rd. Bridge (Dawson County, Georgia)
Built 1980
Bridge over Amicalola Creek on Steelbridge Rd.
Open to traffic

New Steubenville Bridge (Jefferson County, Ohio)
Built 1990
Cable-stayed bridge over the Ohio River on US 22 between Steubenville and Weirton in Steubenville
Open to traffic

Newell Toll Bridge (Hancock County, West Virginia)
Built 1905; rehabilitated 1954
Private suspension bridge over the Ohio River on Golding Street Extension between Newell and East Liverpool
Open to toll traffic

Newport Bridge (Newport County, Rhode Island)
Built 1969
Suspension bridge over East Passage Narragansett Bay on RI 138 in Newport
Open to toll traffic

Newport Bridge (Jackson County, Arkansas)
Built 1930
Cantilevered through truss bridge on AR 367 (formerly US 67) over White River at Newport
Open to two-lane traffic

Newport Covered Bridge (Vermillion County, Indiana)
Built 1885 by J.J. Daniels; rehabilitated 1983
Covered bridge over Little Vermillion River on CR 50 North
Open to traffic

Newport Railroad Bridge (Jackson County, Arkansas)
Built 1938 by the Virginia Bridge Co.
Through truss swing bridge over White River and CR 10 on the Union Pacific Railroad south of Newport
Open to railroad traffic

Newport Road Bridge (Franklin County, Missouri)
Small concrete arch bridge over a branch of Little Boeuf Creek on Newport Road just off MO 100
Open to one-lane traffic

Niangua River MO 64 Bridge (Dallas County, Missouri)
Built 1931
Two-span open-spandrel arch bridge over Niangua River on MO 64 near Bennett Springs
Open to traffic

Niangua River Old US 66 Bridge (Webster County, Missouri)
Built 1924
Pony truss bridge on Route CC (Old US 66) over East Fork Niangua River
Open to traffic

Niangua River Route K Bridge (Dallas County, Missouri)
Built or relocated here in 1936; rehabilitated 1994
Through truss bridge over Niangua River on Route K
Open to traffic

Nichols Street Bridge (Callaway County, Missouri)
Built ca. 1940
Wooden bridge over the KCS Railroad on Nichols Street at the William Woods University campus in Fulton
Open to two-lane traffic

Ninnescah River Bridge (Sumner County, Kansas)
Built 1962
Through truss bridge over Ninnescah River, 2.0 mi. east and 3.8 mi. south of Belle Plaine
Open to traffic

Nix Creek Bridge (Miller County, Arkansas)
Nix Creek Bridge east 9th street Texarkana Arkansas. Built 1950 by Clark Brothers Construction Company.
Stringer bridge over Nix Creek on East 9th Street / US 82
Open to traffic