Pakistan International Airlines PIA (http://www.piac.com.pk) serves numerous domestic destinations and is the only airline to serve the three airports in the north of interest to trekkers or climbers: Chitral, Gilgit, and Skardu. There are usually two flights from Islamabad to these cities daily, but they are often canceled due to bad weather, and often over-booked — show up early to guarantee a seat.
Pakistan Railway (http://www.pakrail.com/) provides passenger rail service. The stations tend not to have their timetables in English, but sales agents can usually explain everything to you. There are several different classes of fares depending on amenities. Foreign tourists and students with an ISIC card can get 25% and 50% discounts, respectively, by first visiting the PTDC Pakistan Tourism Development Corporation office, getting q verification certificate there, and bringing it with them to the train's commercial ticket office which is different from the regular ticket office, but usually close by.
For local transport within cities, auto rickshaws are a cheap and flexible alternative. A development of the bicycle rickshaw, the auto rickshaw is a small vehicle powered by a two-stroke or four-stroke engine. The original gasoline versions constantly emit a stuttering noise and foul blue-black smoke, but many are opting for the CNGcompressed natural gas versions, which are less polluting and a little quieter. Blue-and-yellow auto rickshaws take passengers, other colors tend to be privately owned. Always negotiate a price before entering the rickshaw.
Rickshaws are banned in the capital Islamabad.
A large portion of travel between cities in Pakistan is carried out by bus. Travelling between Karachi and any of the country's other major cities by bus may take days, travel by bus is often the cheapest and most convenient alternative. The Dae-Woo company runs a regular bus service between several major cities, with air-conditioned buses and seats booked one day ahead. While rather unexpensive, they are still almost five times as expensive as the cheap and uncomplicated rides offered by minibuses or larger buses between the major bus stations of the cities. Fares are often though not always paid directly on the bus, there is no aircondition, and sometimes very little knee space, but you get where you are going all the same, and I have never met with anything but kind interest and friendly conversation on my many rides. Buses leave almost incessantly from the major bus stations for all the major cities, and many smaller locations, so booking ahead is neither possible nor necessary on the simpler buses. When travelling between major cities, smaller buses are to be preferred over the larger ones, as the larger ones tend to take up passagers along the way, and therefore travel more slowly.
The situation is similar for local transport. While the organization of local transport may look a little different between cities, there is usually an active bus service running through the city, with varying levels of government control.