Origin
Saint Peters, MO
Morning in Saint Peters on Saturday
Local time
6:58 AM
CDT
Current temp
57°F
Unavailable
Live forecast
Trip from Saint Peters, MO to Affton, MO
Compiled and reviewed by the Trip.ovh planning team at COD Solutions Oy · Last reviewed Apr 18, 2026 · Editorial standards
Drive Time
46m
Distance
34.4 mi
55 km
Drive Score
5/10
Practical drive
Same Day?
Yes, doable
Fuel Cost
$5
one way
EV Charging
Unknown
Best Time to Leave
4 AM
0h 43m
★
6 AM
0h 47m
8 AM
0h 54m
10 AM
0h 49m
12 PM
0h 49m
3 PM
0h 50m
5 PM
0h 54m
8 PM
0h 44m
Estimated drive times based on typical traffic patterns. Actual times may vary with weather, construction, and real-time conditions.
Saint Peters, MO
Wikimedia Commons
Affton, MO
Wikimedia Commons
Trip Overview
The drive from Saint Peters, MO to Affton, MO covers 34.4 miles and takes about 46m behind the wheel. This route is realistic as a one-day drive if you keep your stops efficient.
The route leans on I 270, I 70, MO 30 for much of the mileage, and the overall profile is highway-focused drive. The longest uninterrupted segment is about 15.6 miles on I 270. At current regular gas prices, budget about $5.38 one way before food or hotel costs.
Who Is This Route For?
Weekend Trip
Doable as a same-day drive at 46m. Total distance: 34.4 miles.
Family Friendly
Moderate complexity with 0 natural rest stops along the way.
Solo Traveler
46m drive, comfortable solo distance.
EV Driver
0 DC fast chargers along the route. Coverage: unknown.
First-Time Driver
Mostly highway driving (95%). Some complex stretches to watch for.
Drive Character
This is a 46m highway drive covering 34.4 miles, with most of the trip on I 270 and I 70. The longest continuous stretch is about 15.6 miles on I 270.
Most of the miles stay on highways, which makes pacing and fuel planning easier than turn-by-turn city driving.
There are about 16 navigation steps in the underlying route data, so the final approach matters more than the middle miles.
I 270 is the longest continuous segment at about 15.6 miles.
How Hard Is This Drive?
This is a straightforward highway drive that stays mostly on I 270 and I 70. This route has several spots where lane changes, forks, or exits need your full attention. The trickiest moment comes around 1.2 miles in.
Driving Effort
10/10
Focused - lots of decisions in a short distance, but it is over quickly
Balances navigation complexity with total wheel time.
This is a short but busy drive. With 13 decision points packed into just 34.4 miles, you will need to pay attention to lane changes and exits — but the whole thing is over in 46m.
Where does it get tricky?
The main spots that need attention: at 1.2 miles: Exit ramp - move to the correct lane early. Lane positioning matters here. Multiple destination signs - pick the right one; at 13.6 miles: Exit ramp - move to the correct lane early. Lane positioning matters here. Multiple destination signs - pick the right one; at 13.8 miles: Highway fork - watch signs carefully. Lane positioning matters here.
Critical Maneuvers
5 of 13 key pointsThese are the spots where you need to pay the most attention. Preview them before you drive.
8
1.2 mi into trip
|
~1m in
Take the exit toward MO 79: Elsberry, Louisiana
Exit ramp - move to the correct lane early. Lane positioning matters here. Multiple destination signs - pick the right one
Use the straight / slight right lanes.
Exit 220
Toward MO 79: Elsberry, Louisiana
8
13.6 mi into trip
|
~17m in
Take the exit toward I 270: Chicago, Memphis
Exit ramp - move to the correct lane early. Lane positioning matters here. Multiple destination signs - pick the right one
Use the slight right lane.
Exit 232
Toward I 270: Chicago, Memphis
7
13.8 mi into trip
|
~17m in
Keep slight right at fork toward I 270 South: Memphis
Highway fork - watch signs carefully. Lane positioning matters here
Use the slight right lane.
Toward I 270 South: Memphis
7
29.9 mi into trip
|
~37m in
Take the exit toward MO 30: Gravois Road
Exit ramp - move to the correct lane early. Lane positioning matters here
Use the slight right lane.
Exit 3
Toward MO 30: Gravois Road
9
30.2 mi into trip
|
~38m in
Keep slight left at fork toward MO 30: Saint Louis, Ulysses S. Grant National Historic Site, Gravois Road
Highway fork - watch signs carefully. Lane positioning matters here. Multiple destination signs - pick the right one
Use the left lane.
Toward MO 30: Saint Louis, Ulysses S. Grant Nat...
Towns Mentioned on Route Signs
Based on OSRM destination-sign hints, not a full list of every settlement the road passes.
Between Saint Peters, MO and Affton, MO, road signs point toward Memphis and Ulysses S. Grant National Historic Site.
Memphis
13.6 mi in
|
~17m
Ulysses S. Grant National Historic Site
30.2 mi in
|
~38m
Main Roads
| Road | Distance | Duration |
|---|---|---|
| I 270 | 15.6 mi | 19m |
| I 70 | 13 mi | 16m |
| MO 30 | 4.1 mi | 7m |
| MO 79 | 0.1 mi | <1m |
Longest stretch:
I 270
— 15.6 mi, about 19m
Turn-by-Turn Driving Directions
Step-by-step road directions between Saint Peters, MO and Affton, MO.
1
Start on I 70
1.2 mi
·
1 min
·
I 70
2
Take the exit
0.1 mi
·
15 sec
Exit 220
Toward MO 79: Elsberry, Louisiana
Use the straight / slight right lanes.
3
Keep slight left at fork
384 ft
·
14 sec
Toward MO 79
4
Turn left onto MO 79
0.1 mi
·
11 sec
·
MO 79
5
Take the ramp
0.2 mi
·
18 sec
Toward I 70 East
Use the right lane.
6
Merge onto I 70
12 mi
·
14 min
·
I 70
Use the straight / slight right lanes.
7
Take the exit
0.2 mi
·
12 sec
Exit 232
Toward I 270: Chicago, Memphis
Use the slight right lane.
8
Keep slight right at fork
0.4 mi
·
33 sec
Toward I 270 South: Memphis
Use the slight right lane.
9
Continue on this road
0.1 mi
·
10 sec
·
this road
Exit 232
Toward I 270 South: Memphis
10
Merge onto I 270
16 mi
·
19 min
·
I 270
Use the straight lane.
11
Take the exit
0.3 mi
·
33 sec
Exit 3
Toward MO 30: Gravois Road
Use the slight right lane.
12
Keep slight left at fork
396 ft
·
11 sec
Toward MO 30: Saint Louis, Ulysses S. Grant National Historic Site, Gravois Road
Use the left lane.
13
Merge onto MO 30
4.1 mi
·
7 min
·
MO 30
14
Turn right
38 ft
·
7 sec
15
Turn left
87 ft
·
6 sec
16
Arrive at destination
Where to Stop
Rest stops, refuel points, and overnight suggestions along this route.
Halfway Point
Midpoint
About 17.2 mi from Saint Peters, MO · 21m into the drive
Mid-route town
Meal stop
17 mi into the route
Best for: Lunch, fuel, and a longer reset
This sits close to the middle of the route, so it works well for the longest stop of the day.
Pacing Suggestions
Fuel and coffee
A short stop after about 34 miles helps settle the day before fatigue starts building.
Meal break
The midpoint is around 17.2 miles from Saint Peters, MO, which is a good place for a longer meal and fuel stop.
Arriving in Affton, MO
Allow a few extra minutes for the final approach into Affton, MO if you are unfamiliar with the area.
These stop ideas are pacing suggestions — the exact town or exit can change with traffic, hotel plans, and fuel range.
Fuel & Cost
Regular Gas
$5.38 one way
$10.76 round trip
$3.97/gal
25.4 MPG avg
12 kg CO2
| Fuel Type | $/gal | One Way | Round Trip |
|---|---|---|---|
| midgrade | $4.36 | $5.90 | $11.81 |
| premium | $4.89 | $6.62 | $13.24 |
| diesel | $5.61 | $7.60 | $15.19 |
No toll roads detected on this route.
Drive Cost (one way)
Fuel
$5
Estimated CO2 emission: 12 kg one way. Prices: EIA weekly data, 2026-04-13.
Driving Electric?
About $4 in charging · 0 stops · 67% less CO2
| Vehicle Type | kWh | Stops | DC Fast | Home Charge |
|---|---|---|---|---|
| Average EV | 10.3 | 0 | $3.61 | $1.65 |
| Efficient EV | 8.6 | 0 | $3.01 | $1.38 |
| EV Truck/SUV | 13.8 | 0 | $4.82 | $2.20 |
Gas CO2
12 kg
EV CO2
4 kg (67% 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.
Destination
Affton, MO
Morning in Affton on Saturday
Local time
6:58 AM
CDT
Current temp
63°F
Unavailable
Live forecast
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 warmer at arrival
A meaningful temperature swing is a good cue to rethink layers, water, and how soon you want to arrive.
Road read
46m 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.
Frequently Asked Questions
The drive from Saint Peters, MO to Affton, MO covers 34.4 miles and takes about 46m without stops. Add 15-30 minutes for a fuel or rest stop on longer drives.
The main roads are I 270, I 70, MO 30. Most of the drive stays on highways, so watch for ramps and exits.
This is a comfortable same-day trip.
The midpoint is about 17.2 miles from Saint Peters, MO. Look for rest areas, gas stations, or food options near the halfway mark.
At current regular gas prices, expect to spend about $5.38 one way. This estimate uses 25.4 MPG — your actual cost will vary with your vehicle's fuel efficiency and current gas prices.
Leave by 9 AM and you'll arrive before lunch. Even a 4 PM departure gets you there before dark in summer.
This is a short but busy drive. With 13 decision points packed into just 34.4 miles, you will need to pay attention to lane changes and exits — but the whole thing is over in 46m.
The main spots that need attention: at 1.2 miles: Exit ramp - move to the correct lane early. Lane positioning matters here. Multiple destination signs - pick the right one; at 13.6 miles: Exit ramp - move to the correct lane early. Lane positioning matters here. Multiple destination signs - pick the right one; at 13.8 miles: Highway fork - watch signs carefully. Lane positioning matters here.
Between Saint Peters, MO and Affton, MO, road signs point toward Memphis and Ulysses S. Grant National Historic Site.
Yes. Nearby national parks include Gateway Arch National Park.
How this page is built
Compiled by the Trip.ovh planning team at COD Solutions Oy from open government datasets — OSRM over OpenStreetMap for geometry, EIA for fuel prices, and NPS for national parks. See our methodology for refresh cadence and limitations.
Was this helpful?
Thanks for your feedback!
Your tip has been submitted. Thanks!
/500
Recent Tips
·
Explore More
Continue From Affton, MO
More trips to Affton, MO
Explore more options from Saint Peters, MO or browse trips ending in Affton, MO.
Looking for more statewide routes? Browse MO road trips.