Buffalo, WY to Green River, WY is 351.2 miles and takes about 6h 4m via Dwight D. Eisenhower Highway, with a fuel budget near $55 and enough daylight to finish in a day. This trip stays within Wyoming, connecting two points in the Mountain West region. Expect a mix of highway cruising and surface roads as you make your way south. With a recommended one-day drive time and a moderate fuel cost, this route is a straightforward option for getting between these two Wyoming cities.
Trip Pace
Same-day drive is realistic
A same-day return is possible, but it will make for a full day on the road.
Break Rhythm
1 planned break
Plan on a short reset every 3 to 4 hours to stay fresh behind the wheel.
Midpoint
175.6 miles from Buffalo, WY
A natural place for your longest stop of the day
, about 3h into the drive
.
Main Roads
Road
Distance
Duration
Dwight D. Eisenhower Highway
119.1 mi
1h 55m
I 25
108.1 mi
1h 41m
County Road 308
63.7 mi
1h 12m
US 287
44.1 mi
50m
Casper West Belt
7.3 mi
8m
US 20
2.7 mi
3m
I 80 Bus
1.9 mi
4m
West Spruce Street
1.5 mi
2m
Longest stretch:
Dwight D. Eisenhower Highway
— 119.1 mi, about 1h 55m
Traffic on I-80
Hour-of-day weekday pattern from 12 FHWA count stations on your route.
Peak
4 PM
~664 veh/hr typical
· worst 902
Quietest
2 AM
~94 veh/hr
Peak-to-quiet ratio
7.1×
busier at peak than in the quiet hours
12a6anoon6p11p
Averaged across 52 weeks of 2023 FHWA Travel Monitoring Analysis System data. Weekday hours only (Mon–Fri).
Turn-by-Turn Driving Directions
Step-by-step road directions between Buffalo, WY and Green River, WY.
1
Start on I 25 Bus; US 16; US 87 Bus
1.2 mi·1 min·North Main Street
Use the straight lane.
2
Take the ramp
0.5 mi·1 min
Toward I 25 South, US 87 South: Casper
3
Merge onto I 25; US 87
108 mi·1 hr 41 min·I 25; US 87
4
Take the exit
0.3 mi·42 sec
Toward US 20 West, US 26 West, WY 220 West: Shoshoni, Port of Entry
5
Keep slight left at fork
0.1 mi·17 sec
6
Turn right onto US 20; US 26
2.7 mi·3 min·US 20; US 26
7
Continue on WY 257
7.3 mi·8 min·Casper West Belt
8
Turn right onto WY 220
64 mi·1 hr 12 min·County Road 308
9
Continue on US 287; WY 789
44 mi·50 min·US 287; WY 789
10
Turn right onto I 80 Bus; US 30 Bus; WY 789
1.5 mi·2 min·West Spruce Street
11
Take the ramp onto WY 789
0.6 mi·1 min·WY 789
12
Merge onto I 80; US 30; WY 789
119 mi·1 hr 55 min·Dwight D. Eisenhower Highway
13
Take the exit onto I 80 Bus; US 30 Bus
1.9 mi·4 min·I 80 Bus; US 30 Bus
Toward I 80 Business West, US 30 Business West: Green River
14
Turn right onto North 1st East
35 ft·1 sec·North 1st East
15
Arrive at destination
North 1st East
Trip Plan
Given the 6-hour drive time, leaving Buffalo, WY in the morning will allow you to reach Green River, WY well before evening. The longest stretch without a clear stop point is over 119 miles, so plan for a fuel and rest break before you hit that segment if needed. With only one recommended stop and a fuel cost around $55, this is a manageable one-day drive. Keep an eye on your fuel gauge, especially as you transition off the main highway sections.
Morning Departure
Start early — leave by 6-7 AM to arrive at a reasonable hour.
Evening Departure
This is a long drive — plan for a morning departure or consider splitting it into two days.
You can normally do this drive in one day.
Plan roughly 1 meaningful break for fuel, food, and rest.
The halfway point lands around 175.6 miles from Buffalo, WY, or about 3h into the drive.
The longest continuous stretch on this route runs about 119.1 miles.
This is a comfortable same-day trip.
Departure
Before you leave
Start with fuel, water, and navigation already sorted so the first hour feels easy.
First stop
Around 77 miles or 1h 13m in
Use this first pause for coffee, a restroom break, and a quick traffic check ahead.
Halfway reset
Around 175.6 miles or 3h in
This is the best place for your longest stop, a real meal, and a full fuel check.
Final approach
Final hour starts around 5h 3m
Traffic, exits, and arrival timing usually matter more near Green River, WY than in the middle of the route.
Before You Leave
+
Open the route before leaving Buffalo, WY so your first major turns are already loaded.
+
Leave with enough water and a charging cable within reach, not packed away.
+
Check your fuel range against the first long segment, especially if you are starting outside city service areas.
Day 1
Settle into the route from Buffalo, WY
This is one driving day of about 351.2 miles and 6h 4m.
Your first comfortable stop window is around 77 miles from Buffalo, WY.
This route can stay practical as a one-day drive if traffic stays reasonable.
Plan about 1 real break rather than only quick fuel stops.
The longest stretch is on Dwight D. Eisenhower Highway for about 119.1 miles.
Where to Stop
Rest stops, refuel points, and overnight suggestions along this route.
Place data sourced from public business listings. Hours and availability may vary.
Heads-up: tricky spots
5 of 12
5 decision points cluster between mile 0 and 349.3 — GPS handles the exact turns, but know they're coming. Your lane choice matters more than the turn itself.
4
0 mi into trip|~0m in|I 25 Bus; US 16; US 87 Bus / North Main Street
Depart onto I 25 Bus; US 16; US 87 Bus / North Main Street
Lane positioning matters here
Use the straight lane.
5
1.2 mi into trip|~1m in
Take the ramp toward I 25 South, US 87 South: Casper
Multiple destination signs - pick the right one
Toward I 25 South, US 87 South: Casper
5
109.9 mi into trip|~1h 44m in
Take the exit toward US 20 West, US 26 West, WY 220 West: Shoshoni, Port of Entry
Exit ramp - move to the correct lane early. Multiple destination signs - pick the right one
Toward US 20 West, US 26 West, WY 220 West: Sho...
4
110.2 mi into trip|~1h 45m in
Keep slight left at fork
Highway fork - watch signs carefully
5
349.3 mi into trip|~6h in|I 80 Bus; US 30 Bus
Take the exit onto I 80 Bus; US 30 Bus toward I 80 Business West, US 30 Business West: Green River
Exit ramp - move to the correct lane early. Multiple destination signs - pick the right one
Toward I 80 Business West, US 30 Business West:...
Fuel & Cost
Regular Gas
$54.74 one way
$109.48 round trip
$3.96/gal25.4 MPG avg123 kg CO2
Fuel Type
$/gal
One Way
Round Trip
midgrade
$4.17
$57.70
$115.40
premium
$4.47
$61.86
$123.72
diesel
$4.80
$66.31
$132.63
No toll roads detected on this route.
Estimated Trip Cost (one way, 1 person)
Fuel
$55
Meals
$25–$50
Total
$80–$105
Rough estimate based on US averages. Hotel $80–$140/night, meals $25–$50/day.
Estimated CO2 emission: 122.9 kg one way.
Prices: EIA weekly data, 2026-07-13.
Driving Electric?
About $37 in charging
· 1 stop
· 67% less CO2
Vehicle Type
kWh
Stops
DC Fast
Home Charge
Average EV
105.4
1
$36.88
$16.86
Efficient EV
87.8
1
$30.73
$14.05
EV Truck/SUV
140.5
1
$49.17
$22.48
Gas CO2
123 kg
EV CO2
41 kg (67% less)
Plan for 1 charging stop. A 30-minute DC fast charge mid-route should be enough to complete the trip comfortably.
DC fast charging avg $0.35/kWh. Home charging avg $0.16/kWh. US grid CO2: 0.39 kg/kWh.
Travel Intel
Current conditions at both ends of the drive.
Forecast as of Jul 17, 2026
Origin
Buffalo, WY
Evening
in Buffalo on Saturday
Local time
7:27 PM
MDT
Current temp
64°F
Partly Cloudy
NNW 6 mph2% chanceLive forecast
Flood Watch
Flood Watch issued July 17 at 1:55AM MDT until July 17 at 10:00PM MDT by NWS Riverton WY
Heat Advisory
Heat Advisory issued July 17 at 1:49AM MDT until July 19 at 9:00PM MDT by NWS Rapid City SD
Destination
Green River, WY
Evening
in Green River on Saturday
Local time
7:27 PM
MDT
Current temp
58°F
Mostly Cloudy
NW 3 mph1% chanceLive forecast
Flood Watch
Flood Watch issued July 17 at 1:55AM MDT until July 17 at 10:00PM MDT by NWS Riverton WY
Heat Advisory
Heat Advisory issued July 17 at 1:49AM MDT until July 19 at 9:00PM MDT by NWS Rapid City SD
Seasonal Notes
Summer travel usually means heavier construction, hotter rest stops, and busier weekend traffic around major cities.
Winter travel shortens daylight, so a route that looks manageable on paper can feel much longer after dark.
Holiday weekends tend to make both departure and arrival windows slower than the raw route time suggests.
Time zone
Same local time
Origin and destination are on the same clock, so arrival timing is easier to judge at a glance.
Temperature spread
6 degrees cooler at arrival
A meaningful temperature swing is a good cue to rethink layers, water, and how soon you want to arrive.
Road read
6h 4m on the road
Start early — leave by 6-7 AM to arrive at a reasonable hour.
Weather data from the National Weather Service. Conditions may change; check closer to your travel date.
More Details
What kind of drive is this?
You'll spend about 45% of your time on highways, with the longest continuous stretch covering 119.1 miles on the Dwight D. Eisenhower Highway. After this significant highway portion, the route transitions to surface roads, indicated by the mixed highway and surface profile. Expect a gradual shift from high-speed travel to more rural cruising as you progress.
45% highway, the rest on surface roads — varied driving throughout.
15 navigation steps total — most of the decisions cluster near the start and finish.
Longest single stretch: 119.1 mi on Dwight D. Eisenhower Highway.
How Hard Is This Drive?
4/10
This route mixes highway mileage with some local-road sections near the start or finish. There are only a few real navigation decisions along the way. The trickiest moment comes early in the drive near I 25 Bus; US 16; US 87 Bus / North Main Street.
Driving Effort4/10
Easy - simple navigation with a manageable amount of wheel time
Balances navigation complexity with total wheel time.
The route itself is not hard, but at 6h 4m, endurance matters. Plan breaks every 2-3 hours. The 12 decision points are all manageable with basic attention.
Where does it get tricky?
The main spots that need attention: near the start (I 25 Bus; US 16; US 87 Bus / North Main Street): Lane positioning matters here; at 1.2 miles: Multiple destination signs - pick the right one; at 109.9 miles: Exit ramp - move to the correct lane early. Multiple destination signs - pick the right one.
Elevation Profile
High-altitude sections with notable climbs
7,021 ft4,640 ft
Total Climb
2,776 ft
Total Descent
1,311 ft
Highest Point
7,021 ft
~250.9 mi in
Elevation Range
2,381 ft
Notable High Points
4,741 ft at ~25.1 miles+4 ft prominence
6,268 ft at ~150.5 miles+183 ft prominence
7,021 ft at ~250.9 miles+150 ft prominence
6,945 ft at ~301 miles+208 ft prominence
Towns Mentioned on Route Signs
Based on OSRM destination-sign hints, not a full list of every settlement the road passes.
On the drive from Buffalo, WY to Green River, WY, road signs begin pointing toward Port Of Entry along the way.
The longest stretch is about 119.1 miles on Dwight D. Eisenhower Highway. The full list of main roads is in the Roads section above.
Yes — we found about 8 rest areas or service plazas within a short detour of the route (from OpenStreetMap). See the Rest Stops tab under Nearby Places for locations and mile markers. Plan to stretch, use the bathroom, and top off fluids every 2–3 hours on longer drives.
It helps. This is a long drive, so arriving tired and in the dark compounds. If the last hour of the trip is on surface roads or mountain grades, aim to arrive at Green River, WY before sunset when you can. Check the Trip Plan for departure windows that land you in daylight.
Only with planning. This is a long drive for kids — consider splitting it into two days rather than pushing through. Plan at least 1 meaningful breaks. There are 8 rest areas along the route for bathroom stops.
Mostly yes along the main roads, but rural stretches through WY can have sparse or no coverage. Before you leave, download offline Google Maps or Apple Maps for the route, and consider downloading music or podcasts instead of streaming. If you depend on data for navigation, keep a paper backup of the turn-by-turn directions.
The main spots that need attention: near the start (I 25 Bus; US 16; US 87 Bus / North Main Street): Lane positioning matters here; at 1.2 miles: Multiple destination signs - pick the right one; at 109.9 miles: Exit ramp - move to the correct lane early. Multiple destination signs - pick the right one.
Not recommended in a single day. At 6.1 hours each way, a round trip means 12.2 hours of driving — that is an unsafe level of fatigue for most drivers. Plan at least one night at Green River, WY before the return drive.
