Denizli is a small industrial city in the mountains of southwestern Turkey. It has a population of 513,480 (2009 census) and is the capital city of Denizli Province.
Denizli attracts many visitors to the mineral-coated hillside hot spring of Pamukkale (cotton castle), and the ancient ruined city of Hierapolis, as well as ruins of the city of Laodicea on the Lycus, the ancient metropolis of Phrygia. Also in the district of Honaz about 10 miles west of Denizli is what was, in the 1st century A.D., the town of Colossae.
In summer the weather is very hot, the winters may occasionally be very cold with snow on the mountains that surround the city.

The area has been occupied since prehistoric times, there were important ancient Greek and Roman towns nearby, (Hierapolis and Laodicea on the Lycus), which persisted through the Byzantine period.
As well as the tourist attractions the city of Denizli is known for its textile industry (and outlet shopping for cut-price clothing) and its famous cockerels. The saying goes that Denizli is known for 'kız', 'toz' and 'horoz'; girls (the girls of the Aegean region are famously the fairest in Turkey), dust and cockerels. There are statues and other images of the birds all over the city.

1.1. History
The city was founded in its current location after the area has been settled by the Turks. 300 years ago the Turkish traveler Evliya Celebi visited Denizli and recorded the town as follows: "The city is called (Denizli) (which means seaside in Turkish) as there are several rivers and lakes around it. In fact it is a four day trip from the sea. Its fortress is of square shape built on flat ground. It has no ditches. Its periphery is 470 steps long. It has four gates. These are: painters gate in North, saddle-makers gate in the East, new Mosque gate in the South, and vineyard gate in the West. There are some fifty armed watchmen in the fortress, and they attend the shop. The main city is outside the fortress with 44 districts and 3600 houses. There are 57 small and large mosques and district masjids, 7 madrassahs, 7 children's schools, 6 baths and 17 dervish lodges. As everybody sat in vineyards the upper classes and ordinary people do not flee from each other."

1.2. City Life in Denizli
Denizli is a rapidly growing industrial (mainly textile) and touristic town. It is situated close to the historical and extremely popular tourist sites of Pamukkale, Hierapolis, Laodikeia and Aphrodisias.

The city centre contains all the usual Turkish chain store branches and supermarkets in addition to shops unique to Denizli such as those selling locally hand-produced carpets and rugs. There are 4-screen cinemas both in the city centre and in the nearby EGS shopping centre Forum Çamlık Mall, Teras Park Mall just slightly out of town. Films are generally shown in English with Turkish subtitles.

For football fans, Denizli boasts a large stadium which is home to Denizli’s own successful first-division team, Denizlispor. Both national and international matches are held regularly here.
A variety of restaurants, both small and large, caters for all tastes and bars/cafes/nightclubs are situated both in the city centre and within walking distance of all University centers.
People in Denizli are generally relaxed and friendly and are extremely hospitable to the student population.

1.3. Culture and entertainment
There are large shops, bars and cafes, even some live music, although this is a small city, deep in the countryside and the cinema, music, cafe life etc. cannot compare to İzmir or Istanbul. In time the presence of Pamukkale University will surely improve the cultural amenities of the city. Therefore many private clubs and associations are opening up including: The society for the Protection of the Environment and History of Denizli; The Poets and Poetry Lovers Association; the Pizza Appreciation Group, Teras Park, Forum Çamlık, Baron, Keops, Friends, Sir Winston Tea, Glorias Jeans and the Jazz-rock Local. There is an annual amateur theatre festival, attended by groups from Turkey and overseas. Denizli has the second-largest number of ranking chess-players in Turkey, after Istanbul.

1.4. Twin cities

1.5. Pamukkale
Pamukale, meaning "cotton castle" in Turkish, is a natural site and attraction in south-western Turkey in the Denizli Province. The ancient city of Hierapolis was built on top of the white "castle" which is in total about 2700 meters long and 160m high. It can be seen from a great distance, eg. when driving down the hills on the opposite side of the valley to the town of Denizli, which is 20 km away. Pamukkale is located in Turkey's Inner Aegean region, in the Maeander River valley, which enjoys a temperate climate over the greater part of the year.

The tectonic movements that took place in the fault depression of the Menderes river basin did not only cause frequent earthquakes, but also gave rise to the emergence of a number of very hot springs, and it is the water from one of these springs, with its large mineral content — chalk in particular — that created Pamukkale. Apart from some radioactive material, the water contains large amounts of hydrogen carbonate and calcium, which leads to the precipitation of calcium carbonate. The effect of this natural phenomenon leaves thick white layers of limestone and travertine cascading down the mountain slope, making the area look like a fortress of cotton or a frozen waterfall.

Pamukkale is a very famous tourist attraction of Turkey, and tourists travel from the coast of Antalya and the Aegean Sea to this place as it is one of two World Heritage Sites in Turkey, together with Hierapolis. Only a few other places in the world are somewhat similar, such as the Mammoth Hot Springs in the USA, and HuangLong in SiChuan Province of China (another UNESCO World Heritage Site).

Unfortunately, Pamukkale was abused for decades in the late 20th century, as hotels were built on top of the site, destroying parts of the remains of Hierapolis. The hot water was taken to fill the hotel pools, and the waste water was even spilled over the monument itself turning it brownish. In addition, a tarmac road ramp was built right into the main part. People walked around with shoes, washed themselves with soap and shampoo in the pools, and even rode bikes and motorbikes up and down the slopes.

After UNESCO turned its attention to Pamukkale, and the site was dramatically losing its attraction, the officials finally acted. The hotels were demolished, and the road ramp was covered with artificial pools which nowadays are, unlike the most other parts, accessible to bare-footed tourists. Even tadpoles can be found in there. A small trench was carved along the outside of the ramp, to collect the water and prevent it from spilling in the "wrong" places. These brownish parts are left to be bleached by the sun first, without being covered by water, as this would worsen the problem. Many pools are thus empty. Others parts are covered with water for an hour or two according to a schedule which is on display on top of the hill.

The underground volcanic activity which causes the hot springs, also caused carbon dioxide to seep into a cave which as a result was called the Plutonium (= "place of the god of the dead").