National parks near Union, Missouri
Gateway Arch National Park is the closest national park to Union, Missouri — 46.3 mi (74.5 km) in a straight line, which works out to roughly 1 hr 32 min behind the wheel.
Gateway Arch makes a full day trip — leave early.
Union has a population of about 10,957.
National parks near Union
| Park | Straight-line distance | Estimated drive | Realistic trip |
|---|---|---|---|
| Gateway Arch National Park | 46.3 mi (74.5 km) | 1 hr 32 min | Doable as a day trip |
| Mammoth Cave National Park | 282 mi (453 km) | 7 hr 7 min | Worth a longer road trip |
| Hot Springs National Park | 294 mi (474 km) | 7 hr 25 min | Worth a longer road trip |
| Indiana Dunes National Park | 302 mi (487 km) | 7 hr 37 min | Worth a longer road trip |
| Great Smoky Mountains National Park | 456 mi (733 km) | 11 hr 14 min | Worth a longer road trip |
| Point Pelee National Park | 509 mi (820 km) | 12 hr 30 min | Worth a longer road trip |
| Cuyahoga Valley National Park | 537 mi (864 km) | 13 hr 10 min | Worth a longer road trip |
| New River Gorge National Park | 539 mi (867 km) | 13 hr 12 min | Worth a longer road trip |
| Congaree National Park | 655 mi (1054 km) | 15 hr 57 min | Worth a longer road trip |
| Bruce Peninsula National Park | 672 mi (1082 km) | 16 hr 22 min | Worth a longer road trip |
What to book before you leave Union
| Park | What needs booking | Covers | How |
|---|---|---|---|
| Great Smoky Mountains | Great Smoky Mountains National Park Parking Tag | Parking, not an entrance fee | Timed reservation |
Camping near Union
Within reach of Union, 50 campgrounds across 7 parks appear on Recreation.gov: 30 at Great Smoky Mountains, 5 at Mammoth Cave, 5 at Indiana Dunes, and 5 at New River Gorge, plus 3 more parks with fewer sites.
Recreation.gov releases most national park campsites six months before the arrival date, at 10:00 a.m. Eastern time. Windows are set per campground, so confirm yours on the Seasons and Fees tab on that campground page.
Once a date is gone, cancellations are the real supply, and they get taken within minutes of appearing.
When to make this trip
Gateway Arch National Park is generally best May through October, with April and early November as the quieter shoulder either side.
Winter brings cold, shorter days, and reduced services, though lower-elevation trails often stay walkable.
Peak summer weekends and autumn colour weekends fill parking lots early — arrive before mid-morning.
Seeing more than one
Several parks near Union are close enough to each other to combine on one trip, so the drive from home only has to happen once.
| Pair | Apart | Estimated drive |
|---|---|---|
| Mammoth Cave → Great Smoky Mountains | 179 mi (288 km) | 4 hr 41 min |
Planning a trip from Union
Distances here are straight-line and the drive estimate adds a road factor on top, but mountain passes and seasonal closures can change it a lot — a route that looks like three hours in June can be shut entirely in February. Confirm road status with the park before you commit to a date.
Other towns in Franklin County
Common questions
What is the closest national park to Union?
Gateway Arch National Park. It is about 46.3 mi (74.5 km) from Union, roughly 1 hr 32 min of driving.
Can I do a national park day trip from Union?
Yes — Gateway Arch National Park is within about a three-hour drive.
How many national parks are near Union?
10 parks are within reach of Union, 1 of them close enough for a day trip.
Do you need a reservation for the national parks near Union?
None of them gate the entrance itself. These requirements are usually seasonal, so check the date you plan to arrive.
Where can you camp near Union?
Recreation.gov lists 50 campgrounds at the national parks within reach of Union. They are spread across 7 of those parks.
When is the best time to visit the parks near Union?
For Gateway Arch National Park, the closest one, generally May through October. Either side of that, April and early November stays quieter.