Unionville, MO to Saint Peters, MO is 226.5 miles and takes about 4h 36m via Avenue of the Saints, with a fuel budget near $35 and enough daylight to finish in a day. This drive stays within Missouri, moving from the Midwest region to the Midwest region. You'll spend most of your time on the Avenue of the Saints and US 63, which offer a mix of highway and surface road driving. With only one recommended stop and a manageable duration, this route is ideal for a single-day trip. It's a straightforward path with a clear destination and budget in mind.
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
113.3 miles from Unionville, MO
A natural place for your longest stop of the day
, about 2h 20m into the drive
.
Main Roads
Road
Distance
Duration
Avenue of the Saints
73.7 mi
1h 27m
US 63
54.5 mi
1h 4m
Chicago-Kansas City Expressway
52.9 mi
1h 1m
Main Street
24.5 mi
36m
Dwight D Eisenhower Highway
10.9 mi
13m
V.F.W. Memorial Highway
5.8 mi
6m
Veterans Road
2.1 mi
3m
Paris Gravel Road
0.5 mi
1m
Longest stretch:
Avenue of the Saints
— 73.7 mi, about 1h 27m
Traffic on I-70
Hour-of-day weekday pattern from 12 FHWA count stations on your route.
Peak
3 PM
~3,169 veh/hr typical
· worst 3,683
Quietest
1 AM
~265 veh/hr
Peak-to-quiet ratio
12×
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 Unionville, MO and Saint Peters, MO.
1
Start on US 136
24 mi·36 min·Main Street
2
At end of road, turn right onto US 63
54 mi·1 hr 4 min·US 63
3
Take the exit
0.2 mi·12 sec
Toward US 36 East, MO 110 East: Hannibal
4
Merge onto US 36; MO 110
53 mi·1 hr 1 min·Chicago-Kansas City Expressway
5
Continue on US 24; US 36; MO 110
5.8 mi·6 min·V.F.W. Memorial Highway
6
Take the exit
0.2 mi·30 sec
Toward Veterans Road
7
Turn right onto Veterans Road
2.1 mi·3 min·Veterans Road
8
At end of road, turn left onto County Road 422
279 ft·6 sec·County Road 422
9
Continue on Paris Gravel Road
0.5 mi·1 min·Paris Gravel Road
10
Take the ramp
120 ft·3 sec
11
Merge onto US 61
74 mi·1 hr 27 min·Avenue of the Saints
Use the right lane.
12
Take the exit
0.5 mi·51 sec
Toward I 70 East: Saint LouisUse the slight left / straight lanes.
13
Merge onto I 70
11 mi·13 min·Dwight D Eisenhower Highway
Use the straight / slight right lanes.
14
Take the exit
0.2 mi·19 sec
Exit 222AToward Mid Rivers Mall DriveUse the straight / slight right lanes.
15
Keep slight left at fork
205 ft·4 sec
Toward Mid Rivers Mall DriveUse the slight left lane.
16
Turn straight onto Mid Rivers Mall Drive
198 ft·5 sec·Mid Rivers Mall Drive
17
Take the ramp
0.3 mi·20 sec
Toward I 70 West: WentzvilleUse the slight left lane.
18
Merge onto I 70
479 ft·6 sec·I 70
19
Arrive at destination
I 70
Trip Plan
Given the 4h 36m estimated drive time, leaving Unionville in the morning should allow you to reach Saint Peters well before evening. The estimated fuel cost of $35 is based on the 226.5-mile distance, so plan accordingly. While the route data suggests only one stop, the relatively short duration means you can be flexible. Keep an eye on your fuel gauge, especially during the 73.7-mile stretch on the Avenue of the Saints, as services might be less frequent in certain segments. This is a manageable drive that doesn't require extensive planning for overnight stays.
Morning Departure
An early start around 7-8 AM gets you there with plenty of daylight left.
Evening Departure
A late afternoon start means arriving after dark. Morning is better.
You can normally do this drive in one day.
Plan roughly 1 meaningful break for fuel, food, and rest.
The halfway point lands around 113.3 miles from Unionville, MO, or about 2h 20m into the drive.
The longest continuous stretch on this route runs about 73.7 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 50 miles or 1h 6m in
Use this first pause for coffee, a restroom break, and a quick traffic check ahead.
Halfway reset
Around 113.3 miles or 2h 20m in
This is the best place for your longest stop, a real meal, and a full fuel check.
Final approach
Final hour starts around 3h 47m
Traffic, exits, and arrival timing usually matter more near Saint Peters, MO than in the middle of the route.
Before You Leave
+
Open the route before leaving Unionville, MO 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 Unionville, MO
This is one driving day of about 226.5 miles and 4h 36m.
Your first comfortable stop window is around 50 miles from Unionville, MO.
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 Avenue of the Saints for about 73.7 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 14
5 decision points cluster between mile 78.9 and 226.2 — GPS handles the exact turns, but know they're coming. Your lane choice matters more than the turn itself.
6
78.9 mi into trip|~1h 40m in
Take the exit toward US 36 East, MO 110 East: Hannibal
Exit ramp - move to the correct lane early. Multiple destination signs - pick the right one
Toward US 36 East, MO 110 East: Hannibal
6
214.5 mi into trip|~4h 21m in
Take the exit toward I 70 East: Saint Louis
Exit ramp - move to the correct lane early. Lane positioning matters here
Use the slight left / straight lanes.
Toward I 70 East: Saint Louis
7
225.9 mi into trip|~4h 36m in
Take the exit toward Mid Rivers Mall Drive
Exit ramp - move to the correct lane early. Lane positioning matters here
Use the straight / slight right lanes.
Exit 222A
Toward Mid Rivers Mall Drive
8
226.1 mi into trip|~4h 36m in
Keep slight left at fork toward Mid Rivers Mall Drive
Highway fork - watch signs carefully. Lane positioning matters here
Use the slight left lane.
Toward Mid Rivers Mall Drive
6
226.2 mi into trip|~4h 36m in
Take the ramp toward I 70 West: Wentzville
Lane positioning matters here
Use the slight left lane.
Toward I 70 West: Wentzville
Fuel & Cost
Regular Gas
$33.45 one way
$66.90 round trip
$3.75/gal25.4 MPG avg79 kg CO2
Fuel Type
$/gal
One Way
Round Trip
midgrade
$4.14
$36.93
$73.85
premium
$4.72
$42.05
$84.11
diesel
$4.80
$42.77
$85.53
No toll roads detected on this route.
Estimated Trip Cost (one way, 1 person)
Fuel
$33
Meals
$25–$50
Total
$58–$83
Rough estimate based on US averages. Hotel $80–$140/night, meals $25–$50/day.
Estimated CO2 emission: 79.2 kg one way.
Prices: EIA weekly data, 2026-07-13.
Driving Electric?
About $24 in charging
· 0 stops
· 66% less CO2
Vehicle Type
kWh
Stops
DC Fast
Home Charge
Average EV
68
0
$23.78
$10.87
Efficient EV
56.6
0
$19.82
$9.06
EV Truck/SUV
90.6
1
$31.71
$14.50
Gas CO2
79 kg
EV CO2
27 kg (66% less)
Plan for 0 charging stops, roughly every 270 miles. Allow 25-40 minutes per stop at a DC fast charger.
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 18, 2026
Origin
Unionville, MO
Late night
in Unionville on Monday
Local time
12:54 AM
CDT
Current temp
93°F
Chance Showers And Thunderstorms
W 6 mph28% chanceLive forecast
Heat Advisory
Heat Advisory issued July 18 at 12:07PM CDT until July 18 at 8:00PM CDT by NWS Memphis TN
Heat Advisory
Heat Advisory issued July 18 at 12:07PM CDT until July 19 at 9:00PM CDT by NWS Memphis TN
Destination
Saint Peters, MO
Late night
in Saint Peters on Monday
Local time
12:54 AM
CDT
Current temp
94°F
Mostly Sunny
W 9 mph8% chanceLive forecast
Heat Advisory
Heat Advisory issued July 18 at 12:07PM CDT until July 18 at 8:00PM CDT by NWS Memphis TN
Heat Advisory
Heat Advisory issued July 18 at 12:07PM CDT until July 19 at 9:00PM CDT by NWS Memphis TN
88°F
Independence, IL
113 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
1 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
4h 36m on the road
An early start around 7-8 AM gets you there with plenty of daylight left.
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...
26 mi from route
~66 min detour
$19
near mile 226.5
Park data from the National Park Service API. Alerts update every 2 hours.
More Details
What kind of drive is this?
This drive is about 47% highway, meaning you'll transition from faster speeds to more varied surface roads. The longest continuous stretch on the Avenue of the Saints is 73.7 miles, offering a good period of cruising before you encounter more varied terrain. Expect a mixed profile of highway and surface roads throughout the 226.5-mile trip. You'll notice a shift in your surroundings as you move from more open highway sections to areas with more frequent exits and intersections.
47% highway, the rest on surface roads — varied driving throughout.
19 navigation steps total — most of the decisions cluster near the start and finish.
Longest single stretch: 73.7 mi on Avenue of the Saints.
How Hard Is This Drive?
8/10
This route mixes highway mileage with some local-road sections near the start or finish. This route has several spots where lane changes, forks, or exits need your full attention. The trickiest moment comes around 78.9 miles in.
Driving Effort8/10
Demanding - plan breaks and stay ahead of the key maneuvers
Balances navigation complexity with total wheel time.
This is a demanding drive. With 14 significant decision points across 226.5 miles, you will need to stay alert - especially through interchange areas and urban stretches. Consider splitting it into segments if you are not comfortable with fast highway navigation.
Where does it get tricky?
The main spots that need attention: at 78.9 miles: Exit ramp - move to the correct lane early. Multiple destination signs - pick the right one; at 214.5 miles: Exit ramp - move to the correct lane early. Lane positioning matters here; at 225.9 miles: Exit ramp - move to the correct lane early. Lane positioning matters here.
Doable as a same-day drive at 4h 36m. Total distance: 226.5 miles.
Family Friendly
Moderate complexity with 1 natural rest stops along the way.
Solo Traveler
4h 36m drive, comfortable solo distance.
Scenic Drive
Mixed highway & surface route profile with national parks nearby.
Frequently Asked Questions
The longest stretch is about 73.7 miles on Avenue of the Saints. The full list of main roads is in the Roads section above.
Yes — we found about 2 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 route has a higher-than-average number of complex decision points, which get harder in the dark. If the last hour of the trip is on surface roads or mountain grades, aim to arrive at Saint Peters, MO 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 2 rest areas along the route for bathroom stops.
The main spots that need attention: at 78.9 miles: Exit ramp - move to the correct lane early. Multiple destination signs - pick the right one; at 214.5 miles: Exit ramp - move to the correct lane early. Lane positioning matters here; at 225.9 miles: Exit ramp - move to the correct lane early. Lane positioning matters here.
Yes — Gateway Arch National Park. See the National Parks section for detour distances and tips on detours.
Possible but tiring. At 4.6 hours each way, an in-and-out day trip would put you behind the wheel for 9.2 hours — manageable with a long break at Saint Peters, MO, but most travelers stay overnight.
