Evacuating and escaping a city could become a necessity for various reasons -- a natural disaster, fire, war, or a terrorist attack. Whatever the reason, your decision to evacuate should be based on a valid, logical reason. Cities teem with civilization and offer access to myriad useful resources. Thus, they should not be abandoned unless staying would put you in obvious and imminent danger. It's almost always the better decision to make sure you're well protected and supplied in your city home.
Highways and roads present both opportunities and dangers. If you leave ahead of others who plan to do the same, taking a main highway is likely to be the single fastest means of escape. However, trying to leave by the main freeways during an evacuation event or just before or during a major disaster can be a nightmare, and you might find yourself trapped or the victim of a severe accident in a panicked rush. In that case, you will probably have better odds taking secondary roads, and it would be wise to plot a non-highway route in advance.
If you have access to a boat or can get yourself on a ship leaving port in your city, a city's waterway offers a very useful escape route. Most people don't own their own boat, but as a means of escaping crowds and traffic, evacuation by boat cannot be beaten. Leaving by ship might be much more difficult as others will be searching for space on the same vessel, so plan ahead and arrive early. Of course, this escape route is not recommended in the event of an imminent tsunami.
This may be the safest and easiest means of leaving a city that's facing disaster. No matter how large the fleeing crowds, you're unlikely to have trouble with movement. However, it would be a good idea to have a cross-country escape route mapped out in advance, and to bring plenty of supplies with you. Also, crossing over land on foot, by horse, off-road vehicle or by bike can be very dangerous if desperate evacuees begin to rob or steal. The slow pace of a cross-country escape exposes you much more to this danger.
Trying to leave via the major airports, train stations or bus depots is almost certain to be a poor choice unless you've booked your tickets long in advance and with a reliable provider. Also, depending on the nature of the disaster, these escape options might be cancelled because of infrastructure damage or weather conditions.
