How far is New Underwood, SD from Keystone, SD?

The driving distance from New Underwood, SD to Keystone, SD is about 42.9 miles (69 km), with a travel time of about 00h 54m by car.

  • The straight-line flight distance is about 32 miles (51.5 km).
  • For a round trip, plan for roughly 01h 49m of driving time before adding stops, traffic, or weather delays.
  • A comfortable departure window is usually 8:00 AM to 10:00 AM MDT.
Trip Tools

Reverse, save, or send this route

This route works well as a day trip with time at the destination. Copy the route link, send it to another device, or print a clean version before you head out.

Reverse Route
Quick Snapshot
Road
42.85 mi
00h 54m
Flight
31.99 mi
51.49 km direct

This route works well as a day trip with time at the destination.

Learn Distance

Choose another destination from New Underwood.

Flight Distance

Direct air line
31.99 mi
Kilometers
51.49 km
Flight Time
00h 03m

Driving Distance

Road route
42.85 mi
Kilometers
68.96 km
Drive Time
00h 54m

Gas Cost Calculator

Leave and Arrive Planner

Pick a departure time to see your estimated arrival and same-day return window.

Drive time stays fixed at 00h 54m.

Arrival Snapshot
Arrive in Keystone
Sun, Apr 19, 8:11 AM MDT
Return by in New Underwood
Sun, Apr 19, 9:06 AM MDT
Useful when you're deciding between a quick errand, a day trip, or a longer stop.
Leave New Underwood
2026-04-19T07:17
Arrive Keystone
Sun, Apr 19, 8:11 AM MDT
Route Timing
00h 54m
One way by road
Best Departure Window
8:00 AM to 10:00 AM MDT
Aim for a morning departure
Arrive between
8:55 AM to 10:55 AM MDT

A morning start gives you useful time at the destination and keeps the return out of the late evening.

Leave by
4:40 PM MDT
Keeps a same-day return open with about 03h 00m at the destination.
Back in New Underwood
9:30 PM MDT
Morning start is best

You are leaving earlier than the recommended window, which gives you extra margin for breaks and traffic.

Halfway Point

A useful midpoint for breaks, coffee, or meeting in the middle.

Mid-route stop
Rapid Valley
SD

Census-designated place in Pennington County, South Dakota

From New Underwood
21.4 mi
00h 27m
To Keystone
21.4 mi
00h 27m

Route Weather Snapshot

Check the forecast at both ends before you head out.

Origin
63°F
Sunday

Sunny

Starts
Sun, Apr 19 6:00 AM MDT
Wind
6 to 16 mph E
Destination
62°F
Sunday

Sunny

Starts
Sun, Apr 19 6:00 AM MDT
Wind
3 to 8 mph S

Driving Route Map

The map below follows the saved road route between New Underwood and Keystone.

Turn-by-Turn Driving Directions

Step-by-step road directions between New Underwood and Keystone.

  1. 1

    Start on South A Avenue

    1084 ft · 32 sec · South A Avenue

  2. 2

    Turn right onto Highway 1416

    1895 ft · 43 sec · Highway 1416

  3. 3

    Turn left onto 161st Avenue

    3020 ft · 1 min · 161st Avenue

  4. 4

    Take the ramp left

    1621 ft · 40 sec

  5. 5

    Merge slight left

    15.9 mi · 16 min

  6. 6

    Take the exit slight right toward US 16 Truck, ND 79 South: Mount Rushmore, Crazy Horse

    1470 ft · 36 sec

  7. 7

    Keep slight left

    869 ft · 23 sec

  8. 8

    Continue on North Elk Vale Road

    5.4 mi · 7 min · North Elk Vale Road

  9. 9

    Continue on East Catron Boulevard

    1.2 mi · 2 min · East Catron Boulevard

  10. 10

    Continue on Catron Boulevard

    2.2 mi · 3 min · Catron Boulevard

  11. 11

    Turn left onto Mount Rushmore Road

    1.1 mi · 1 min · Mount Rushmore Road

  12. 12

    Continue on South Highway 16

    12 mi · 14 min · South Highway 16

  13. 13

    Take the exit slight left

    2.7 mi · 5 min

  14. 14

    Turn left onto Reed Street

    1913 ft · 1 min · Reed Street

  15. 15

    Continue on 1st Street

    155 m · 20 sec · 1st Street

  16. 16

    Turn right

    28 m · 7 sec

  17. 17

    Arrive at your destination

    0 m · 1 sec

Car Route Details

A richer read on the saved driving route between New Underwood and Keystone.

OSRM road route
Drive Character

Turn-heavy local drive

The route has frequent decision points for its length, so lane choice and turn timing will matter more than cruising speed.

Directions
17 steps
5 turns on the saved route
Ramps & Exits
4
1 merges, 3 ramps or exits
Navigation Density
39.7 / 100 mi
Decision points by distance
Main Roads
161st Avenue
16.8 mi · 39%
South Highway 16
14.7 mi · 34%
North Elk Vale Road
5.37 mi · 13%
Catron Boulevard
2.25 mi · 5%
East Catron Boulevard
1.21 mi · 3%
Mount Rushmore Road
1.09 mi · 3%
Longest Stretch

161st Avenue

Merge slight left

15.9 mi · 00h 16m

Route Summary

A quick read on whether this route feels easy, ambitious, or worth planning around.

Trip Read

A comfortable day-trip route

This route works well as a day trip. You can leave in the morning, spend meaningful time at the destination, and still return the same day.

Drive Time
00h 54m
Day trip friendly
Same-Day Return
01h 50m
Round-trip wheel time
Road vs Air
+10.9 mi
32 mi direct line
Halfway Stop
Rapid Valley
00h 27m from New Underwood
Leave By
4:40 PM MDT
Morning start is best
Weather Watch

Sunny leaving New Underwood and Sunny near Keystone.

Trip Questions

Direct answers travelers usually want before committing to the drive.

How long does it take to drive from New Underwood to Keystone?

The road trip is about 42.9 miles (69 km) and usually takes 00h 54m in normal driving conditions.

Is this a same-day trip or an overnight route?

This route works well as a day trip. You can leave in the morning, spend meaningful time at the destination, and still return the same day.

What is the halfway point on this route?

Rapid Valley is a useful midpoint, sitting about 21.4 miles from New Underwood and 21.4 miles from Keystone.

How much longer is the road route than the straight-line distance?

The direct path is about 32 miles (51.5 km), while the road route adds roughly 10.9 extra miles because roads do not follow the straight air line.

When is the best time to leave for this route?

A good departure window is usually 8:00 AM to 10:00 AM MDT. If you want a more comfortable same-day return, try to leave by 4:40 PM MDT.

How much will gas cost for this route?

Using about 28.3 MPG, regular gas is estimated at $5.69 one way or $11.39 round trip. Estimated CO2 is about 13.4 kg one way.

What should you check before leaving?

Before you leave, expect Sunny around New Underwood and Sunny near Keystone.

Stop Ideas Near Rapid Valley

Useful break, food, and waypoint ideas within about 15 miles of the route midpoint.

Mid-route Guidance
These suggestions come from reviewed places and nearby services around Rapid Valley and the surrounding midpoint area.
Willow Park
Scenic stop 3.7 mi away

Willow Park

Rapid City , SD
155 Monroe St, Rapid City, SD 57701
Rating 4.1/5 35 reviews Park,Playground
Stop photo coming soon
Meeting point 7.6 mi away

Box Elder City Hall

Box Elder , SD
420 Villa Dr, Box Elder, SD 57719
Rating 5.0/5 2 reviews City government office
Stop photo coming soon
Nearby stop 7.6 mi away

Box Elder Water Department

Box Elder , SD
420 Villa Dr, Box Elder, SD 57719
Rating 2.3/5 3 reviews Water utility company

Transit and Meeting Points

Useful pickup, handoff, or rendezvous points close to Rapid Valley.

Transit stop coverage is not ready for this midpoint yet.

Flight Path Map

This map shows the direct air route between New Underwood and Keystone. Straight-line distance: 31.99 mi (51.49 km).

Photo coming soon

#1 New Underwood

Human settlement in Pennington County, South Dakota, United States of America

Population679
Coordinates44.0933200, -102.8362800
Altitude867
CountryUnited States
Keystone

#2 Keystone

Town in Pennington County, South Dakota

Population352
Coordinates43.8955400, -103.4182500
Altitude1320
CountryUnited States
Start: New Underwood (-102.83628, 44.09332)
End: Keystone (-103.41825, 43.89554)

Estimated Travel Time

Distance: 69 km by road

SpeedTime
30 mph (48.3 km/h)01h 25m
40 mph (64.37 km/h)01h 04m
50 mph (80.47 km/h)00h 51m
60 mph (96.56 km/h)00h 42m
70 mph (112.65 km/h)00h 36m
80 mph (129 km/h)00h 32m

Fuel, Round Trip and CO2

Estimated fuel cost and emissions for this route.

One-way fuel
1.51 gal
5.72 L · about $5.69
Round trip
$11.39
3.02 gal · 11.44 L
Estimated CO2
13.4 kg one way
Round trip: 26.8 kg / 59 lb CO2, using regular gasoline.
Fuel$/galOne wayRound trip
Regular gas $3.77 $5.69 $11.39
Mid-grade $4.25 $6.42 $12.84
Premium $4.65 $7.03 $14.06
Diesel $5.30 $8.01 $16.02

Assumes 8.3 L/100 km (about 28.3 MPG). CO2 is an estimate and varies by vehicle, fuel blend, traffic, and terrain.

Prices in South Dakota · Apr 19, 2026

There is no time difference between New Underwood and Keystone. The current time is 07:17:03.

Distance to Other Cities

Planning a road trip? See the full trip guide on Trip.ovh — stops, fuel costs, weather, and departure timing.

How did we calculate? Place names are translated into coordinates. The Haversine formula calculates straight-line distance; driving distance uses road network data.