Climbing steep mountain roads may make your engine overheat, so according to the City of Colorado Springs, which is in the southern region of the Rockies, it's important to take steps to make sure your engine stays cool:

If your car is struggling while heading up toward the summit, shift into a lower gear so that you can maintain a consistent speed.
Turn off your air conditioning and roll your windows down if you're traveling up a particularly steep grade, since running the AC puts an additional strain on your engine that may cause it to overheat.
When you've reached that scenic mountain overlook, give your car a chance to cool down by letting the engine idle for a few minutes.
If you can't immediately pull over, you can turn on your car's heater to its highest setting — as you would on a freezing-cold morning. According to Jalopnik, this can help to "bleed off" some of the engine's extra heat, which might buy you some time until you can safely pull over.

If your car starts to run hot, find a safe place to stop so it can cool down before continuing your climb, says the National Park Service. Use pull-off areas whenever possible, but if stopping on the road is unavoidable, the City of Colorado Springs says to look for a straightaway or another spot where approaching motorists will be able to see you clearly. Check your owner's manual for information on how to cool your engine down and what type of coolant to add if needed. Also, do not remove the radiator cap until the engine is cool.