All visitors flying directly to Colorado from abroad must have a proper visas in place before arrival. The US government requires every visitor to have a visa, so enquire with your local US embassy for the exact requirements. Travelers who are already in the US can enter the state of Colorado without any border crossing check. Visit the US government website on visas to learn more http://travel.state.gov/visa/.
Health and Safety
Mother Nature creates most of the health and safety concerns in Colorado. The Rocky Mountains environment can be challenging and the climate extreme. From skiing to mountain biking, be sure your skills match the terrain because there aren’t many medical facilities deep in the mountains and the bill for being airlifted to Denver for medical treatment can be very expensive. That said, there are excellent medical clinics in nearly every tourist town in the state.
In Colorado, the weather can be a major troublemaker. Winter storms dump feet of snow at the drop of a hat and create dangerous driving conditions. Summer is no gentler, as afternoon thunderstorms arrive frequently and suddenly most days. If you are hiking above the tree line, the threat of lightning strikes is very real, as is hypothermia if it rains or even snows. Always be prepared for any conditions when you head out into the mountains for a day of adventure.
Crime is rarely an issue in Colorado. In many small towns people don’t even take the keys out of their trucks. But in Denver it pays to be safe and keep your valuables tucked away when wandering around LoDo after dark. Petty theft can happen anywhere, especially in cars with obvious rental license plates. Never leave anything of value in plain site.