Is there a train from Castle Rock to Denver?

No, there is currently no direct passenger rail service between Castle Rock and Denver.

How long is the drive to Denver?

The drive is approximately 45 km and takes 40 to 60 minutes.

Does the RTD bus run on weekends?

RTD service on the 137 route is primarily focused on weekday peak hours.

Where is the Castle Rock transit center?

It is located near the intersection of 4th Street and Jerry Street.

Is I-25 the only way to get to Denver?

I-25 is the most direct route, though Highway 85 is an alternative for local traffic.

Castle Rock

Denver

Bus Driving

Castle Rock to Denver

Updated: 28 May 2026

The journey from Castle Rock to Denver covers 45 km primarily via Interstate 25 North. Driving typically takes 40 to 60 minutes depending on rush hour congestion near the Tech Center. You can also utilize the RTD bus service, specifically the 137 route, for a reliable public transit option. The route traverses the rolling hills of the Palmer Divide before descending into the Denver metropolitan basin. This corridor serves as the primary artery for thousands of daily commuters heading into the state capital.

Total Distance: 45 km driving distance; 42 km straight-line air distance.

Fastest Way

Driving via I-25 North during off-peak hours takes 40 minutes.

Cheapest Way

RTD bus at $5.25 per one-way ticket.

Compare Castle Rock to Denver Routes

	Bus Direct	Driving Direct
Duration	1 hour 10 mins	45 mins
Avg Price	$5.25	$8 - $12 in fuel
Operator	RTD Denver	Personal Vehicle
Route	Route 137 from Castle Rock Transit Center to Union Station	I-25 North
Tip	Check the RTD mobile app for real-time bus tracking to avoid waiting at the outdoor transit center.	Use the HOV/Express lanes if you have a transponder to bypass heavy traffic near Lone Tree.

Travel Tips

Traffic Timing
Avoid I-25 between 7:00 AM and 9:00 AM to escape the worst of the Denver-bound commute.
Parking
Use the SpotHero app to find discounted parking garages in downtown Denver.
Weather Prep
Always keep a light jacket, as Denver temperatures can drop quickly after sunset.
Transit Pass
Purchase a MyRide card to simplify fare payments on all RTD buses and trains.
Navigation
Use Google Maps or Waze to monitor real-time accidents on the I-25 corridor.

Safety Tips

Road Conditions
Watch for black ice on the I-25 bridges during winter months.
Emergency Kit
Keep a basic emergency kit in your car, including water and a blanket.
Public Transit
Stay aware of your surroundings when waiting at the Union Station bus bays at night.
Speed Limits
Adhere strictly to speed limits in the construction zones often found near Monument and Castle Rock.