Interstate 84 in Utah

Interstate 84 in Utah


Get started Snowville
End Echo
Length 120 mi
Length 193 km
Idaho5 State Route 30

7 Snowville

12 Frontage Road

16 23600 W Road

17 21480 W Road

20 Frontage Road

24 Blue Creek

26 State Route 83

32 Frontage Road

39 W 1000 N

40 Tremonton

41 → Ogden / Pocatello

80 → Salt Lake City

81 South Ogden

85 Ogden Regional Medical Center

87 → Ogden / Salt Lake City

92 Morgan County Airport

96 Peterson

103 Morgan

106 Rees Lane

108 Frontage Road

111 N 5800 E

112 State Route 86

115 Henefer

120 → Salt Lake City / Evanston

Interstate 84 or I -84 is an Interstate Highway in the U.S. state of Utah. The highway forms a diagonal east-west route in the north of the state, running from the Idaho border at Snowville to Interstate 80 at Echo, not far from Salt Lake City. Between Tremonton and Ogden, the route is double -numbered with Interstate 15. Interstate 84 is a total of 193 kilometers long, 130 kilometers of which are not double-numbered with I-15.

Travel directions

The I-15/84 fork at Ogden.

Just north of the immense Great Salt Lake, Interstate 84 crosses the Utah border in Idaho. You pass through a remote area with hardly any villages. It is only at Tremonton that one returns to civilization in an irrigated agricultural valley. Interstate 15 from Pocatello merges here. Both roads will then be double-numbered over 63 kilometers and will initially have 2×2 lanes. One passes by Brigham City and then comes to the somewhat larger town of Ogden. On the south side of Ogden, Interstate 84 exits southeast while I-15 continues south to Salt Lake City. I-84 then passes through the high Wasatch Range via a low mountain pass, where the highway passes through two canyons. The interstate then slowly ascends to the village of Echo, where the road ends at Interstate 80, the route from Salt Lake City to Cheyenne in Wyoming.

  • ANSWERMBA: Provides information about Utah geography.


Originally the US 30S was the through connection in this corridor. Before 1930, only the section between Tremonton and Ogden was tarmac, which largely coincided with US 91. Between the border with Idaho and Tremonton, the route was only slightly improved and unpaved. Also, the route from Ogden to Echo was still partly unpaved. The asphalting of the US Highways was given the highest priority in the early 1930s and by 1937 the entire route was paved.

Between Snowville and Tremonton, I-84 is mostly built directly over or adjacent to the older US 30S. This includes significant portions of the route between Ogden and Echo, which is largely through canyons. Before construction of I-84 started, a small section between Ogden and Uintah had already been widened to 4 lanes. This includes the section between Brigham City and Ogden, which coincides with the later I-15.

Construction of I-84

Construction of I-84 began briskly after the creation of the Interstate Highway system in 1956. As early as 1959, the first section opened around Blue Creek, which was doubling the existing US 30s due to flat terrain. It is possible that this area did not have grade-separated connections at the time, this part is located in an area that had virtually no roads at that time. It was believed to be Utah’s first stretch of Interstate Highway to open. In 1960 a second section opened a little further west through remote area near Snowville. The first eastern section at Morgan also opened to traffic in 1960.

In 1966 the section opened through the Weber canyon east of Ogden. This then connected to US 89 in Uintah and not yet to I-15. A year later, a section opened up through a canyon east of Morgan to Devil’s Slide. By the late 1960s, I-84 was made up of several fragmented sections, with the 25-mile (40-kilometer) section from Uintah to Devil’s Slide east of Ogden being the longest through-passage route.

In 1971, the interchange with I-80 at Echo opened to traffic, being the first interchange of I-84 to open. About 1973, the Tremonton bypass opened to traffic, mostly part of I-15, but also a small portion of I-84. Also in 1973, the last missing section opened between Devil’s Slide and Henefer, allowing I-84 to pass through between US 89 at Ogden and I-80 at Echo. A year later, Ogden’s southern diversion opened to traffic, allowing traffic on I-84 to directly reach I-15. At that time, there was still one missing section of I-84, northwest of Tremonton.

The last missing link at Tremonton took a relatively long time. Tremonton thus became a household name in Utah, as both I-15 and I-84 at Tremonton were one of the last missing highways in the state. This section was not opened to traffic until September 1986.

Opening history

from nasty length date
Exit 20 1940 W Road Exit 26 State Highway 83 10 km 00-00-1959
Exit 7 Snowville (East) Exit 16 Hansel Valley Road 14 km 00-00-1960
Exit 103 Morgan Exit 106 Rees Lane 5 km 00-00-1960
Exit 26 State Highway 83 Exit 32 Ranch Exit 10 km 00-00-1962
Exit 96 Peterson Exit 103 Morgan 11 km 00-00-1962
Exit 87 Uintah Exit 92 Mountain Green 8 km 00-00-1966
Exit 92 Mountain Green Exit 96 6 km 00-00-1967
Exit 106 Rees Lane Exit 111 Devil’s Slide 8 km 00-00-1967
Exit 0 Idaho state line Exit 5 Snowville (west) 8 km 00-00-1970
Exit 16 Hansel Valley Road Exit 20 1940W Road 6 km 00-00-1971
Exit 115 Henefer Exit 120 I-80 8 km 00-00-1971
Exit 5 Snowville (west) Exit 7 Snowville (East) 3 km 00-00-1972
Exit 40 Tremonton (west) Exit 41 I-15 (north) 2 km 00-00-1973
Exit 111 Devil’s Slide Exit 115 Henefer 6 km 00-00-1973
Exit 80 I-15 (South) Exit 87 Uintah 11 km 00-00-1974
Exit 32 Ranch Exit Exit 40 Tremonton (west) 13 km 00-09-1986

Road number history

The original 1956 Interstate Highway plan approved only the western portion between the Idaho border and I-15 at Tremonton. This section was temporarily renumbered I-82S in 1957. That same year, the eastern section between Ogden and Echo was added so that through traffic from I-80 to the northwestern United States would not have to make the detour via Salt Lake City. The entire route was renumbered I-80N in 1958. Much of I-84 was originally constructed and signposted under this number. I-80N made up the entire route from Portland, Oregon to Echo, Utah. In 1977 the route was renumbered to I-84, at that time almost the entire highway was already open to traffic.

Traffic intensities

7,000 vehicles drive daily on the Idaho border, slowly rising to 10,000 vehicles off I-15 at Tremonton. 19,000 vehicles drove south of I-15 at Ogden, dropping to 13,000 vehicles at Morgan and 8,000 vehicles at the end of the highway at Echo.

Interstate 84 in Utah