Kos is the third largest of this group of islands and the second most popular and touristy island after Rhodes. It is located between Kalymnos and Nysiros. It is very well organised and has everything in terms of tourism infrastructure.
The shores of Kos Island are washed by the waters of the Aegean Sea. Its coastline is 112 km long and is caressed by long immaculate beaches, leading to its main industry being tourism. Farming is the principal occupation of many of the island's inhabitants, with their main crops being grapes, almonds, figs, olives, and tomatoes, along with wheat and corn. Cos lettuce may be grown here, but the name is unrelated.
The main villages of Kos island are Kos Town, Kardamena, Kefalos, Tingaki, Antimachia, Mastihari, Marmari and Pyli. Smaller ones are Zia, Zipari, Platani, Lagoudi and Asfendiou.
Throughout its history, the island has been known by the Greek Kos. A person from Kos is called a "Koan" in English. Kos has also been called İstanköy by the Ottomans and Coo by the Italians and was formerly known as Stanchio in English.
The Kos International Airport Hippocrates (KGS)  is located in the centre of the island near the village of Antimachia.
There are daily flights from Athens airport by Olympic Air  and Aegean Airlines . During the months of July and August Astra Airlines  flies from Thessaloniki.
Ryanair  offers flights all year around from Frankfurt-Hahn and Milan-Bergamo to Kos, prices can be as low as about €30 for a return flight. Summer flights from other destinations (e.g. Oslo-Rygge) are available too.
From May till October charter airlines fly directly to Kos from many European airports.
The bus from the airport to Kos Town is on the left of the aiport, takes 1h via Mastichari and costs 3,60€. Ticket is to be made on board. Buses are synchronised with Ryanair arrivals. You can find buses timetable Here.
There is a Carrefour supermarket just outside the airport, less than 5 min walking from the terminal. It's a good and cheap option for a snack or last time souvenirs as they sell local products like olive oil, honey, wine etc. To get there just follow the only road out of the airport, walk a bit up the hill and find the shop on your left hand.
It is also possible to take a ferry from Turkish coasts, Bodrum and Datça. To Bodrum there is the faster Hydrofoil boat (from €30 one-way, passenger only) or the slower ferry operated by the Bodrum Ferryboat Association  (passenger/car/caravan: €28/100/200)
Kos is a relatively plain island, therefore it is suitable to be discovered by bike. Rental offices will offer you bikes for as low as 5€ per day. A good network of bicycle paths is also present, both in the urban network of Kos Town and along the northern coast towards Tigaki and Marmari. You can also bike to Thermes beach passing by Psalidi beach and Agias Fokas beach, the end of the route is especially scenic. See MapMyRide - Kos
Buses run often from Kos Town towards all other main island villages. Two bus stations are present in Kos Town: one, by the port, is for the urban and sub-urban buses (e.g. #1 to Ag.Fokas, #5 to Thermae); the second, inside town (Pisandrou, by Venizelou), is where the island buses stop, including the one for the airport, that passes through Mastichari. Schedules change every 30 days, so be careful if you travel across different months. See 1. All tickets are to be made on board accept of the local busses leaving from the terminal at Akti Miaouli St. (by the port) - where it's cheaper to buy in the ticket booth.
By the port you will also find the tourist train that for 5€ will give you a two-way 15-minutes ride to the Asklepeion, by the village of Platani.
Scooters, ATVs and cars can be hired from many places. You will find a lot along Vassileos Georgiou Boulevar and on Hamirlou St. close to marina. For a 50cc scooter, the daily fee is 15€; some discount if foreseen for longer rentals (3 or 7 days). Most of the places will ask 45/40 for 3 days rentals. It's possible to rent a scooter for 35EUR for 3 days in a place at the corner of Okikonomou and Makrigianni streets (SE part of town). In most of the places for 15EUR you can rent cheap chinese scooters (like Kymco) but these machines are good enough so going for more expensive options has little sense. There is quite a lot of accidents involving tourists so always remember to ask for a helmet and use it. Fuel is not included (around 1,80-1,90 €/lt, i.e. around 10€ for a round trip of the island, around 90 km). Renting ATV remember that it's highly fuel consuming and is quite expensive option.
To have a general idea check prices at: Trust Kos.
Note that due to recent enforcement of rules by the police you will need an international license to hire a scooter on the islands and most of the quality operators will not rent to you without one.
The main port and population centre on the island, also called Kos, is also the tourist and cultural centre, with whitewashed buildings including many hotels, restaurants and a small number of nightclubs forming the famous Kos town "barstreet". The town has main legacies of the dominations by the Knights Hospitaller of Rhodes (1315-1523), the Ottomans (1523-1911) and the Italians (1911-1943). In the urban network you will find several archeological fields, where reperts from Greek and Roman times have been excavated and exposed. The ruins of the Ancient Gymnasium feature 17 columns. The ancient Odeon is very well preserved, together with the Roman House. The Knights' domination left an imponent castle by the port (ticket: 3€), while the Ottomans adorned the town of several Mosques and fountains. The Italian domination may be noted by some early-XX century buildings, among which the Venetian-style palace, by the port, that now houses the local Police and Tribunal.
The ancient physician Hippocrates is thought to have been born on Kos, and in the center of the town is the Plane Tree of Hippocrates, a dream temple where the physician is traditionally supposed to have taught. The limbs of the now elderly tree are supported by scaffolding. The small city is also home to the International Hippocratic Institute and the Hippocratic Museum dedicated to him.
Some 5 km out of Kos town, the Asklepeion (temple of Asclepius, hospital and medicine academy) was once the training place for Hippocrates (entry ticket: 4€; tourist train from the port: 5€ A/R)
Following the coast from Kos Town towards north-east and passing the cape of Agios Fokas (beautiful and less frequented pebbles beach, ), one reached Thermae at the end of the paved road. Here, after a steepy descent, on the beach thermal waters come out at a temperature of around 40-50°C all year round (bus #5 from the port, 1,50€ for the bus ticket bought in the ticket booth, 2€ if bouth onboard; free entrance on the thermal beach) . Please note that the last bus going back from Thermas beach is leaving the spot at 16.30, if you want to stay longer you would have to walk back along the road to MichaelAngelo Hotel (15/20min) from where buses leave to Kos Town until late (lat one is close to 23).
Kardamena, on the south-east coast, is a popular resort for young British holidaymakers and has a large number of bars and nightclubs.
The beaches of the Kefalos istmus (south-west of the island) are the most renowned; among these is Paradise beach. Kefalos is near the only capital of the island, Astipalia, and holds the ruins of a castle.
Snorkeling - Independent snorkeling is probably the best close to Kefalos, especially on Agios Stefanos beach. There is lot's of rocks under water, visibility is very good and quite a lot of marine life to observe.
Sailing in Kos (Yacht Charter in Kos), G.Papandreou Avenue, Kos Marina, 85300, ☎ +30 22420 22195, . The island of Kos is a top yacht charter destination in Greece. You can start your sailing experience from Kos and follow any possible route to other magnificent islands. The marina of Kos is located at the old harbour and is known worldwide since it has been available to skippers and yachting enthusiasts for over a decade. It has been described as one of the hottest cruising areas in Europe as it fulfills every need for any type of boat, such as: fuel/petrol, speedboats, WC-showers, bilge & sewage pump out, waste disposal and many more. Istion Yachting is your ideal sailing provider in Kos. Visitors and tourists can find a wide selection of yachts and catamarans and suggestions about sailing itineraries from Kos to all the surrounding islands and Turkey coasts.edit
Hot Spring There is a hot spring located on the SE coast where hot water and bubbles flow out into the sea, the section of the beach has had a small pool dug out with a little break water where the sea crashes and sprays over that makes for a great experience. Access is by car or public bus, for public bus go to the bus station that is just north of the "Aktis Art Hotel" along the waterfront.
Carrefour has three locations around Kos town: the biggest one is by the main road leading from Kos town to Zipari around 5km out of town. Smaller Carrefour supermarkets are close to the corner of Porfiriou and Ethnikis Antistaseos in the northern part of town and in Zipari on the main road.
Lidl is located on the main road around 5km out of Kos town soon after Carrefour and is one of the largest supermarkets on the island.
Larger AB is located on the main road near Zipari and smaller ones on Ethelonto Paleon Palamiston street and off Makrigianni street.
There is a comparatively large Vassiliadis Supermarket located on Verioupoulou Street (from the harbour you go up Meg. Alexandrou Street, take the second right, continue, cross Omirou Street and you will find Vassiliadis Supermarket on your left (can't miss it you will see the trolleys outside). (Might close of Sundays)
Larger tourist supermarkets
Supermarket Konstantinos is located in Kos town on Ethelonto Paleon Palamiston street and in the towns of Tigaki and Marmari.
There are a few larger style supermarkets dotted around Kos Town. One is the Agora Supermarket located on the corner of Harmilou Street and Artemisias Street, just off from the Marina. Agora Supermarket is open all year round. It has a wide range of products (including cheese, ham, bacon, drinks, fruit and some vegetables). (Open 7 days, 10 a.m. to 10 p.m.). BEWARE - very expensive.
In general small local shops found in less touristic zones (=further from the shore) would have better prices. Fruit Corner located at the corner of Plastira and Makrigianni St. in the SE part of town is one of them.
If you're on a budget, there is pita gyros for € 2,5 sold by most restaurants (some for 2€, e.g. at Shangri-La on square Diagora), to be accompanied by a pint of Greek beer for 1,50-2,00€. In general, try to look for the cheaper and not-that-super-touristic places a bit further from the beachside street. Usually 2-3 blocks should be enough.
Mummy's Cooking Restaurant (Evdokia), 13 Bouboulinas, Kos Towns (near Dolphin Square)). Tavern with traditional Greek food. Let mummy's son help you decide what to order and be surprised how good it all tastes. He tends to pick expensive choices so ask for the price in advance.Reasonable prices, f.e. Moussaka 7€. edit
Restaurant Alexandros, Irakleous, Kos Town (city center, near church with bright blue, illuminated cross on the steeple, walk up the stairs). Tavern with traditional Greek food. Almost every night full, but just keep trying if there is a place free. It is worth it.Reasonable prices, f.e. Moussaka 6€. edit
Meraklis Corner, corner of Patr. Germanou/Antimachou, Kos Town (in the northern part of town, between the beach an Averof St.). Family run Tavern with traditional Greek food and owners little daughter hanging around. Very friendly owners and mouth watering food. They have delicious grilled octopus and fried squid. Also huge grilled meat mix plate for only 9€. Gyros 2€. Live music on Friday nights. Reasonable prices, f.e. main dishes 6-8€. edit
Taverna Antonas, corner of Grigoriou E'/G. Ioannidi, Kos Town (in the eastern part of town, quite close from the beach). Great local atmosphere, mostly Greek customers, ran by elder local gentelmen. You can feed neighbourhood cats with you leftovers. Highly recommended for tipical unspoiled local experience. Reasonable prices, f.e. main dishes around 8€. edit
Grill Bar, corner of Makrigianni/G.Ioannidi, Kos Town (close to Taverna Antonas). Great frilled meat and gyros dishes.edit
Posidonia Restaurant, Kardamena (from the centre of Kardamena take south until Arciri Hotel. The restaurant is by the beach.), ☎ 00302242091430. A family-run restaurant 5 minutes south from the centre of Kardamena, with a very nice and peaceful terrace directly on the beach. Reasonable prices and home cuisineMoussaka 7€. edit
Aegean Restaurant, Kardamena Port, ☎ +30 22420 92224, . Offering greek and international cuisine, on the centre of Kardamena Port. The menu includes a big variety of dishes with meat, vegetables, cheeses and marine dishes with fishes, prawns, squids, lobsters.edit
Three brands of Greek beers are present on the island: Alpha, Mythos and Fix. The most international taste is the one of Amstel, produced in Greece under license from the Dutch company (50cl: 1,10-1,40€ in shops, 2,00-3,50€ in restaurants and bars). Ouzo (similar to sambuca) is the local strong drink, to be served together with snacks and with a glass of water (2,00€). Don't miss Retzina which is white (in most cases) wine flavoured with pine resin, very tipical.
Kos' barstreet is formed by a couple of intersecting streets enclosed by the port and the ruins (Nafklirou) . Usually very calm during the day, the area becomes bustling as from 12pm until morning, with lots of North European adolescents strolling through. Bars and clubs are very similar and the music is only very mainstream. Waiters and bar touts will approach you in the very moment you enter the area, by asking "where are you from" and offering supposedly advantageous deals (e.g. two beers and two shots for 6€); just turn them down.
For a more local experience, try Alsos bar on Epicharmou st.  Here local elderly men gather all day long to chat, have an ouzo or watch the match. The owner will gladly welcome off-the-beaten-track tourists too. Ouzo 2€, beer 2€, Greek salad 4€.
For a more hardcore local experience, try Retro Cafe on Sp. Oikonomou st. close to the corner with Laoumzi. You'll find strictly greek cilentele. Local men playing cards and waching football in TV.
For a modern local experience try "Zero cafe-bar" on Irodotou 1 st.
 Just a few meters from the harbor. Mostly preferred by local youngsters.Artistic design,nice coffee & drinks.
Mix&Match Coctail Bar, Psalidi (3km from Kos town), ☎ 22420 45854, . 18:00 until 03:00. MIX & MATCH cocktail bar, steak house and sushi corner is located in Psalidi area and is adjusted to Zona Club.edit
Zona Club, Psalidi (3km from Kos town), . ZONA CLUB offers the ultimate night-life experience. Enjoy live music events, theme nights, mainstream sounds and dance music. edit
Aegean Houses Hotel (Hotel in Kos), Ethelonton Palaion Polemiston, Lambi, Kos, ☎ +30 22420 48410, . checkin: 14:00; checkout: 12:00. One of the most beautiful Kos hotels, Aegean Houses is a combination of traditional and modern architecture, 300 metres from the sandy beach. (36.907288,27.27967)edit
Ampavris Hotel, (Kos Town), ☎ +30 22420 25780, . A family-run hotel, located in Ampavris area on a small hill just a short distance walk from Kos Town with nice view. edit
Artemis Hotel, (Lambi, Kos Town), . Artemis hotel apartments is located in Lambi area, just 1km from the harbour and Kos town center. The most popular beach of Kos island is just 150m away.edit
Gaia Hotels, (Kos City, Mastichari, Tigaki), ☎ +30 22420 25804, . A hotel chain with four resorts hotels located in Kos.edit
Katras Hotel Apartments, (Tigaki), ☎ +30 22420 68238, . It is located in Tigaki and consists of 55 sunny rooms.edit
Leonidas Hotel and Studios, Sintagmatos Dodekanision st., (Kos Town), ☎ 00302242026921, . Leonidas Hotel and Studios is the most popular 2 star hotel and the first discount hotel on Kos island. Price for a Double Room from 15€/night. edit
Michelangelo Resort & Spa Hotel, Agios Fokas, Kos 85300, ☎ +30 2242045810 (firstname.lastname@example.org, fax: +30 2242045825), . A modern hotel with rooms and suites with views to the sea and gardens.edit
Sunny Days Hotel, (Tigaki), . It is situated at Tigaki of Kos 500 meters from the beach.edit
Nissia Kamares Hotel Apartments, Kardamena (Close to the church), ☎ +306936207428, . checkin: 12:00; checkout: 11:00. Built in a very distinctive traditional Greek island style, Nissia Kamares Hotel Apartments comprises 38 studios and apartments on two floors.Varies. (36.78176639244232,27.140661478042603)edit
Marianna hotel apartments, Tigaki Kos, ☎ 2242049943,2242069090, . checkin: 14.00; checkout: 12.00. Cozy studios and apartments by Marianna 3 star hotel in Kos, Greece.65€. (36.882576,27.186191)edit
Diamond Hotel, . Kos Island ís premier 5 star hotel Diamond Deluxe, brings a new notion to Greek Islands Hotels, as a top luxury boutique hotel in the Dodecanese islands in Greece.edit
Kipriotis Panorama Hotel&Suites, Psalidi (3km from Kos town), ☎ 2242057000, . checkin: 14:00; checkout: 12:00. Luxurious 5* hotel offering comfortable rooms with stunning views. It is located just 200 meters from the sea and 3 km from Kos Townedit
Kipriotis Village Resort, Psalidi (3km from Kos Town), ☎ 2242055300, . checkin: 14:00; checkout: 12:00. Beach front 4* family resort offering great facilities for children and adults. edit
Kipriotis Maris Suites, psalidi (3km from Kos town), ☎ 2242024401, . checkin: 14:00; checkout: 12:00. 5-star luxury hotel offering superb accommodation for leisure travellers. The residents can enjoy the facilities of Kipriotis hotels complex including 2 holistic wellness spa, 4 tennis courts,basketball and volley court,amusement park, water-slides (upon charge)etc edit
Kipriotis Hippocrates Hotel, psalidi (3km from Kos town), ☎ 2242024401, . checkin: 14:00; checkout: 12:00. This 4 star hotel is right next to the beach of Psalidi, 3km from kos town. It offers spacious rooms with porch, as well as 2 pools and a palm-tree garden.edit
Kipriotis Panorama Aqualand, Psalidi (3km from Kos town), . checkin: 14:00; checkout: 12:00. This 4 star family friendly hotel has an Aqualand park with water-slides to entertain the little ones. The extra large rooms offer stunning views to the Aegean sea.edit
Diamond Deluxe Hotel, Nea Alikarnassos, Lambi 85300 Kos, Greece, ☎ +30 22420 48835, . Diamond Deluxe Hotel, the new premier 5 star hotel can only be described as a haven of luxury and style, situated on the Dodecanese island of Kos in Greece.edit
Almost all cafés and restaurants in town offer wi-fi access. Connection quality may vary, though.
The Cafe - Bar "Zero" (1,Irodotou st.,Kos Town;0030 22420 20182) offers free "wi-fi" access plus laptops & tablets for freeaswell.Open all year round.
The internet-café e-Global (2, Artemisias st., Kos town; 0030 22420 27911) has internet, printing services, and even consolle games. Smoking is allowed inside, unfortunately. Open until 1am. Discounted tariffs for members (internet: 2,50€/h, printing: 0,20€/page b/w)
You will find another internet cafe on Alexandrou St. close to the corner with Eleftheriou Venizelou.