Potosi, MO to St. Louis, MO is 72.1 miles and takes about 1h 39m via MO 21 and I 55, with a fuel budget near $11 and enough daylight to finish in a day. This drive takes you from the Midwest region of Missouri to another part of the Midwest, staying within the same state for the entire journey. It's a relatively short trip, making it a straightforward option for a quick excursion or a segment of a larger road trip. You can expect a practical, highway-focused experience for most of this drive.
Trip Pace
Same-day drive is realistic
A same-day return is realistic if you keep stops short.
Midpoint
36 miles from Potosi, MO
A natural place for your longest stop of the day
, about 55m into the drive
.
Main Roads
Road
Distance
Duration
MO 21
22.6 mi
36m
I 55
20.5 mi
22m
Rosa Parks Highway
12.5 mi
15m
US 67
6 mi
7m
MO 110
4.2 mi
5m
South Tucker Boulevard
1.3 mi
3m
South Main Street
1.1 mi
1m
Amvets Drive
1.1 mi
2m
Longest stretch:
MO 21
— 22.6 mi, about 36m
Turn-by-Turn Driving Directions
Step-by-step road directions between Potosi, MO and St. Louis, MO.
1
Start on MO 8
1.0 mi·1 min·West High Street
2
Turn left onto MO 21
23 mi·36 min·MO 21
3
Turn right onto Amvets Drive
1.1 mi·2 min·Amvets Drive
4
At end of road, turn left onto South Main Street
1.1 mi·1 min·South Main Street
5
Turn right onto Fountain City Road
0.8 mi·1 min·Fountain City Road
6
Turn right onto MO 110
4.2 mi·5 min·MO 110
7
Take the ramp
0.3 mi·18 sec
Toward US 67 North: Festus, Crystal City
8
Merge onto US 67
5.7 mi·6 min·US 67
9
Keep slight right at fork onto US 67
0.3 mi·27 sec·US 67
10
Take the exit
0.3 mi·49 sec
Toward I 55 North: Saint Louis
11
Merge onto I 55
21 mi·22 min·I 55
12
Continue on I 55
12 mi·15 min·Rosa Parks Highway
Use the straight / slight right lanes.
13
Take the exit
0.2 mi·23 sec
Exit 207AToward MO 30 East: Gravois AvenueUse the slight right lane.
14
Turn slight right onto Gravois Avenue
0.2 mi·27 sec·Gravois Avenue
15
Continue on South Tucker Boulevard
1.3 mi·3 min·South Tucker Boulevard
16
Turn right onto Market Street
86 ft·2 sec·Market Street
17
Arrive at destination
Market Street
Trip Plan
Given the short duration of just under two hours, this trip offers great flexibility. You can easily depart at any time of day, making it ideal for a spontaneous outing. There are no designated stops mentioned, so plan for fuel and rest before you leave Potosi or as needed in St. Louis. Keep an eye on your fuel gauge, as the estimated cost is around $11, suggesting a focus on efficient travel rather than long, scenic detours. The longest uninterrupted stretch is on MO 21, so if you prefer to break up driving, that's a good segment to consider a brief pause before hitting the interstate.
Morning Departure
Leave by 9 AM and you'll arrive before lunch.
Evening Departure
Even a 4 PM departure gets you there before dark in summer.
You can normally do this drive in one day.
You may only need one short stretch break if traffic stays light.
The halfway point lands around 36 miles from Potosi, MO, or about 55m into the drive.
The longest continuous stretch on this route runs about 22.6 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 16 miles or 25m in
Use this first pause for coffee, a restroom break, and a quick traffic check ahead.
Halfway reset
Around 36 miles or 55m in
This is the best place for your longest stop, a real meal, and a full fuel check.
Final approach
Final hour starts around 1h 24m
Traffic, exits, and arrival timing usually matter more near St. Louis, MO than in the middle of the route.
Before You Leave
+
Open the route before leaving Potosi, MO so your first major turns are already loaded.
Day 1
Settle into the route from Potosi, MO
This is one driving day of about 72.1 miles and 1h 39m.
Your first comfortable stop window is around 16 miles from Potosi, MO.
This route can stay practical as a one-day drive if traffic stays reasonable.
The longest stretch is on MO 21 for about 22.6 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 11
5 decision points cluster between mile 23.6 and 70.4 — GPS handles the exact turns, but know they're coming. Your lane choice matters more than the turn itself.
4
23.6 mi into trip|~38m in|Amvets Drive
Turn right onto Amvets Drive
Navigation decision point
5
24.7 mi into trip|~40m in|South Main Street
At end of road, turn left onto South Main Street
Navigation decision point
5
30.7 mi into trip|~49m in
Take the ramp toward US 67 North: Festus, Crystal City
Multiple destination signs - pick the right one
Toward US 67 North: Festus, Crystal City
4
36.7 mi into trip|~56m in|US 67
Keep slight right at fork onto US 67
Highway fork - watch signs carefully
7
70.4 mi into trip|~1h 35m in
Take the exit toward MO 30 East: Gravois Avenue
Exit ramp - move to the correct lane early. Lane positioning matters here
Use the slight right lane.
Exit 207A
Toward MO 30 East: Gravois Avenue
Fuel & Cost
Regular Gas
$11.27 one way
$22.54 round trip
$3.97/gal25.4 MPG avg25 kg CO2
Fuel Type
$/gal
One Way
Round Trip
midgrade
$4.36
$12.38
$24.75
premium
$4.89
$13.87
$27.75
diesel
$5.61
$15.92
$31.84
No toll roads detected on this route.
Estimated Trip Cost (one way, 1 person)
Fuel
$11
Meals
$25–$50
Total
$36–$61
Rough estimate based on US averages. Hotel $80–$140/night, meals $25–$50/day.
Estimated CO2 emission: 25.2 kg one way.
Prices: EIA weekly data, 2026-04-13.
Driving Electric?
About $8 in charging
· 0 stops
· 68% less CO2
Vehicle Type
kWh
Stops
DC Fast
Home Charge
Average EV
21.6
0
$7.57
$3.46
Efficient EV
18
0
$6.31
$2.88
EV Truck/SUV
28.8
0
$10.09
$4.61
Gas CO2
25 kg
EV CO2
8 kg (68% less)
This trip is well within single-charge range for most EVs. No charging stops needed if you start fully charged.
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 Apr 15, 2026
Origin
Potosi, MO
Night
in Potosi on Saturday
Local time
11:35 PM
CDT
Current temp
56°F
Unavailable
Live forecast
Destination
St. Louis, MO
Night
in St. Louis on Saturday
Local time
11:35 PM
CDT
Current temp
74°F
Unavailable
Live forecast
56°F
Crystal City, MO
36 mi in
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
18 degrees warmer at arrival
A meaningful temperature swing is a good cue to rethink layers, water, and how soon you want to arrive.
Road read
1h 39m on the road
Use the two city cards together: check the sky where you start, then compare it with the local time and temperature at arrival.
Weather data from the National Weather Service. Conditions may change; check closer to your travel date.
National Parks Near This Route
Worth a detour if your schedule allows.
Gateway Arch National Park
National Park
Gateway Arch National Park commemorates President Jefferson’s vision of a continental nation, the individuals and cultural groups who helped shape its history, St. Louis’ role in westward expansion, a...
Established by 1750, Ste. Geneviève was the first permanent European settlement in Missouri. Early French Canadian settlers were drawn here by the rich agricultural land known as Le Grand Champ (the B...
24 mi from route
~61 min detour
Free
near mile 36.4
Park data from the National Park Service API. Alerts update every 2 hours.
More Details
What kind of drive is this?
This route is primarily a highway-focused drive, with 74% of the journey utilizing major roadways like MO 21 and I 55. You'll encounter a longest stretch of 22.6 miles on MO 21, offering a consistent pace before merging onto the interstate. While much of the drive is on faster roads, the initial section on MO 21 provides a slightly different feel before transitioning to the more direct path of I 55. Expect a generally efficient and direct travel experience on this particular route.
74% highway — fuel and pacing are the main things to plan.
17 navigation steps total — most of the decisions cluster near the start and finish.
Longest single stretch: 22.6 mi on MO 21.
How Hard Is This Drive?
5/10
This is a straightforward highway drive that stays mostly on MO 21 and I 55. You will hit about 11 points where you need to pay attention to lane position or signs. The trickiest moment comes around 23.6 miles in near Amvets Drive.
Driving Effort5/10
Moderate - straightforward overall, but long enough or busy enough to require pacing
Balances navigation complexity with total wheel time.
This drive requires moderate attention. Across 72.1 miles you will encounter 11 spots where lane choice or exit timing matters. Not difficult for experienced highway drivers, but worth previewing the tricky sections before you go.
Where does it get tricky?
The main spots that need attention: at 23.6 miles (Amvets Drive): Navigation decision point; at 24.7 miles (South Main Street): Navigation decision point; at 30.7 miles: Multiple destination signs - pick the right one.
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 Potosi, MO to St. Louis, MO, road signs begin pointing toward Crystal City along the way.
The Gateway City of St. Louis is the epitome of the modern Midwestern metropolis. Missouri's second-largest city is vibrant but laid-back, populous but navigable, historic but still relevant. The city's planners have created an aesthetically beautiful city, with plenty of green space amidst buildings both old and new, framed by the majestic Mississippi and Missouri rivers. And capping it all is the world's tallest man-made monument, the beautiful and iconic Gateway Arch.
St. Louis is a city of culture and surprisingly inexpensive. Among American cities, only Washington, D.C. has more free attractions for tourists and residents alike. Hotels, restaurants, and even parking garages avoid the premium pricing common in other big cities. Although often overlooked, St. Louis can be an affordable, educational, and fun family getaway.
Doable as a same-day drive at 1h 39m. Total distance: 72.1 miles.
Family Friendly
Moderate complexity with 0 natural rest stops along the way.
Solo Traveler
1h 39m drive, comfortable solo distance.
First-Time Driver
Mostly highway driving (74%). Some complex stretches to watch for.
Frequently Asked Questions
The longest stretch is about 22.6 miles on MO 21. The full list of main roads is in the Roads section above.
Yes. At under 2 hours behind the wheel, this works well for families — plan one quick stop if you have younger kids.
The main spots that need attention: at 23.6 miles (Amvets Drive): Navigation decision point; at 24.7 miles (South Main Street): Navigation decision point; at 30.7 miles: Multiple destination signs - pick the right one.
Yes — Gateway Arch National Park and Ste. Geneviève National Historical Park. See the National Parks section for detour distances and tips on detours.
Yes. A round trip is manageable in a single day if you plan a break at St. Louis, MO before heading back.
