Kansai International Airport was built at exorbitant cost on an artificial island in Osaka Bay, some 40 kilometers to the south of the city of Osaka. Unlike Tokyo's Narita, Kansai has fairly good domestic connections throughout Japan, making it a good choice for transiting onward. However, if you're flying domestically and your final destination is in Kansai, it probably makes more sense to fly to the more centrally-located Osaka (Itami) or Kobe airports instead.
The airport's single terminal, designed by star Italian architect Renzo Piano, is reputedly the longest building in the world at 1.7 kilometers, over one mile, from end to end. Arrivals are on the 1st floor, while departures are from the 4th floor. On arrival, note that not all ATMs accept foreign cards, but the Citibank and post office ATMs do. There are several currency exchanges in the arrivals and departures areas. They will only handle transactions from or to Japanese yen. Reliable baggage delivery services are available at the north and south ends of the international arrivals area.
The most practical means of getting to Osaka and Kyoto is by train. All trains leave from the Kansai Airport station across the road from the arrivals hall; there is a clearly marked walkway on the 2nd floor. ICOCA/PiTaPa smart cards are valid for travel to/from the airport, and can be purchased from and returned to its ticket offices; see Kansai for more details. You have a choice of two companies operating a total of four services:
West Japan Railway's Haruka.
The JR West Haruka limited expresses run from the airport to Tennoji (29 min, ¥1,760), Shin-Osaka (45 min, ¥2,470) and Kyoto (73 min, ¥2,980). The fares listed are for non-reserved ordinary seats. Trains run every 30-60 minutes, some services make additional stops and/or continue onward to Maibara.
The Haruka is the easiest and fastest way to reach Kyoto, and you can connect to the Shinkansen (bullet train) at Shin-Osaka.
The Japan Rail Pass can be used for the Haruka. You can exchange your rail pass voucher for the pass itself at the JR ticket counter.
JR Rapid Service
The JR Rapid Service runs along the same tracks to Tennoji (43 min, ¥1,030), but then diverge along the Osaka Loop Line to Osaka station (63 min) and terminus Kyobashi (72 min, ¥1,160). All seats are non-reserved and trains depart every 20 minutes; the trains can get crowded at rush hour.
The Rapid Service is convenient for connections onward towards Kobe or Kyoto; change trains at Osaka station. Note that the Rapid Service does not go to any Shinkansen stations; to get to Shin-Osaka, you must transfer at Osaka to a local or rapid train bound for Kyoto.
Some trains from Osaka split with only some carriages proceeding to Kansai, and the others proceeding on the main line.
Nankai Railway's rapi:t.
The Nankai rapi:t trains run to Namba station in Osaka. rapi:t α, taking 29 minutes from Kansai to Namba, stops at Shin-Imamiya, Tengachaya, Izumisano, and Rinku Town, while rapi:t β takes 34 minutes with stops at Sakai and Kishiwada. Both trains cost ¥1,390 to Namba, including a ¥500 reservation surcharge, and one or the other runs every 30 minutes.
The rapi:t and Rapid Service are the recommended means of going to central Osaka.
Nankai Rapid Service
Nankai Rapid Service trains run along the same tracks to the same destination, but like their JR counterparts stop more often and may get crowded. The trip to Namba takes 42 min and costs ¥890, making this the cheapest of the four options, unless your final destination is a JR station in Osaka (e.g. Universal City). If you are considering a multi-day Kansai rail pass, consider this before buying your ticket, as it includes transport on the Nankai Rapid Service (not rapi:t). You can buy multi-day Kansai rail passes at the information desk at the airport.
Airport Limousine buses  leave for various destinations throughout Kansai from the 1st floor directly outside the arrivals hall. The cost is comparable to or slightly higher than the train, but the buses go directly to some major hotels (service to Umeda-area hotels is approximately 60 minutes; ¥1,300) and can be faster than the train for some destinations such as Kobe (60 minutes, ¥1,800) in good traffic.
The bus is also the only practical option for connecting to domestic flights from Osaka's Itami Airport (70 minutes, ¥1,700).
After a prolonged hiatus, Kaijo Access  restarted their high-speed ferry service in 2006 and now run directly to Kobe's airport. Ferries run roughly every 45 minutes and take 29 minutes one way (¥1500). Via the ferry, shuttle bus and the Port Liner AGT line, Sannomiya (central Kobe) can be reached in one hour.
Taxis are very expensive except shuttle vans. Going to Osaka will cost you a minimum of ¥16,000, while reaching Kyoto will rack up closer to ¥32,000.
By shuttle van
Shared shuttle van services are provided by taxi companies at much more reasonable rates than private taxis. (MK Taxi) , (KIX HP - Shared shuttle van services) charges only ¥2,300 per person to Kobe or ¥3,000 to Kyoto, including one suitcase and carry-on luggage (there's a 1,000 yen additional charge if you have more than one large item). Convenient as it's a door-to-door service, but since the driver has 9 people to deliver, it may not be a fast arrival. Reservation at least two days beforehand is necessary, either online or by phone (tel. +81-75-702-5489, open 8 AM to 9 PM).
The Sky View (tel. 072-455-2082) is open year round. Shuttle buses run from the passenger terminal building, and take about 6 minutes (¥100 adults, ¥50 children). There is an observation deck (8am - 10pm), an amusement floor (weekdays 10am - 6pm, weekends 10am - 8pm), a restaurant floor (11am - 10pm, last call 8pm), and a shopping floor (10am - 8pm).
Kanku Lounge (tel. 072-455-2092, open 24 hours),  On the second floor. Basic lounge open to all visitors, offering massage, PC desks, shower booths (¥500), women's room, kids' play room and business center. ¥300 for the first 30 min, then ¥600/hour.
Refresh Room (tel. 072-455-2792, open 9am - 9pm, reception to 8pm), in the international departure area (4F), offers coin-op "electronic" massage chairs (¥200 for 10 minutes), regular massage chairs for ¥500 per hour, shower rooms (¥600 for 30 minutes, towels and soap included) and personal lounges with beds for ¥1,000 per hour (¥500 per hour thereafter).
The Kids Room (tel. 072-455-2791 open 9:30am - 6:30pm), also in the international departure area (4F), has facilities for children from infants to seven years old, accompanied by a parent or guardian. The playroom, infant room and nursing room are free, and complimentary baby food and diapers are offered (one per child).
There are nursing rooms on the second, third and fourth floors, inside the womens' restrooms, and near the domestic and international gates.
Business Center (tel. 072-456-7151, open 8am - 8pm) 4th floor.
Coin-Operated Photo Booths ,4th and 2nd floor.24th opened.700 yen.
Prayer room, in the international departure area (4F), near "Refresh Room".
Post Office , 2nd floor, . The ATM here accepts international credit cards. Open 8am - 9pm (weekday) 9am - 5pm (Saturday,Sunday and Public Holidays).
The Aeroplaza (3F) features several stores, including Uniqlo for cheap, foreigner-sized clothing.
Rinku Premium Outlets / Aeon Rinku Shopping Center, 3-28 Rinku-ourai-minami, Izumisano 072-458-4600, 10am to 8pm, . There are over 150 shops and restaurants. A shuttle bus runs from the north end of the international arrivals area outside the first floor of the airport. It takes about 10 minutes and costs ¥100. By taxi,it is about ¥3,000 from airport.
Sky Shop Town, on the same shuttle bus route, is in the Sky View (see above) area.
Hotel Nikko Kansai (see below) also features an upscale gift shop.
Numerous duty-free shops populate the international departures gate area.
There are two convenience stores at the north end of the Passenger Terminal building (2F) and the Aeroplaza (1F).
The Aeroplaza (3F) is filled with eateries and shops for passengers who wish to do some last minute shopping. Although not as atrocious as some other international airports, prices may be slightly higher than on the mainland. At the arrival hall and on the departure floor, there are a few Starbucks coffee shops (open until 10pm).
There are 47 restaurants in the Passenger Terminal , primarily on the 2nd and 3rd floors. Generally, these are less expensive than the airside options.
Matsuya (松屋) (3F) is a cheap Japanese fast food staple, open 24 hours, offering beef bowls.
551 HORAI (2F). A Chinese restaurant featuring "Butaman" - a pork meat pie something like piroshki, famous in Osaka.
In the international departures area, your options are limited to Cafe KANSAI (レストラン カフェ カンサイ) (7AM-1AM) and Blue Sky (8AM-9:30PM), located in the central area near the south wing shuttle. Both have a variety of small meals, beverages, and take-away snacks. The selection is limited relative to the landside portion of the terminal - if you have extra time, consider eating before going through the security checkpoint.
For slightly cheaper eats, try the shops on the main floor of the hotel building. This area is also a good place for gift shopping, and has several other amenities such as a video arcade. Food and retail outlets usually close by 10 PM.
In the Aeroplaza (3F), there is a basic "Japanese-style pub".
Hotel Nikko Kansai is the only other place for a pre-flight drink, with bars on the 11th floor.
Budget travellers: on the terminal 4th floor, there is a variety shop called AIR ROUT, which sells beer and shochu-based drinks (chu-hai) at regular Japanese prices (about $2 per can, much cheaper than most options), if you are satisfied to sit in general areas and drink beer.
The airport terminal is open 24/7, so you can sleep in there. Blankets are also available from the information centers for free (until 11pm).
If you're willing to pay a bit extra, the Kanku Lounge offers a 9-hour package for ¥3800.
There are several hotels across the bridge near Rinku-Town Station, 6 minutes away by JR or Nankai. For most tourists it hardly seems worth using them, since once you have boarded the train, you might as well go to your final destination, but they can come in handy for early morning departures or overnight connections.
Kansai Airport Washington Hotel, 1-7 Rinku-Orai-Kita, Izumisano, tel. 072-461-2222, . Over 500 rooms, rack rate for a single ¥9500, discounts available for advance bookings. 3 min on foot from Rinku-Town station, or take a shuttle bus from the airport.
Ramada Kansai Airport, 3-3-34 Ichibanishi, Izumisano, tel:072-461-2222, . Over 500 rooms, rack rate ¥8000, advance booking discounts available. 10 min on foot from Rinku-Town station, or take a shuttle bus from the airport.
Sun Plus Hotel, 3-3-4 Minato, Izumisano, tel. 0120-48-2911, 072-461-2911. Single rooms ¥6,300 yen. Free pick up service from Rinku-Town Station, and free delivery to the airport.
Hotel Nikko Kansai Airport
There is only one hotel on the artificial island itself:
Hotel Nikko Kansai Airport, tel. 072-455-1111 . Single rooms from ¥22,000yen, advance booking discounts available. Directly connected to the airport by a walkway, and featuring restaurants, a wine bar, a business center, etc. Airline crews use this hotel. It is possible to get a room "free" as part of a JAL international flight if there is no connecting flight on the day you arrive.
Across the bridge in Rinku Town:
ANA Gate Tower Hotel Osaka, tel. 072-598-8511 . 56-story hotel run in cooperation with InterContinental Hotels. Single rooms from ¥12,600yen, advance booking discounts available.
Small internet kiosks are available throughout the airport. In the arrivals building, they cost ¥100 for 15 minutes, but once you're through the gates in the international departures area, access is free - look for the e symbol "information" computers .
There is also free wireless internet  access in many parts of the terminal building.
If you're feeling unwell, there is a health clinic (tel. 072-456-7185; 9am - 5pm regular hours, emergency treatment available 24 hours) on the second floor provided by Kinki University Hospital.
There is a hospital at Rinku-Town (about 10 minutes by car), Rinku General Medical Center, with English, Portuguese, Chinese and Spanish-speaking staff. (tel. 072-469-3111) 
But if the ill feelings are confined to your teeth, then see the dental clinic (tel. 072-456-8601; open weekdays only, 9:30am - 1pm, 2pm - 7:30pm) on the third floor. Walk-ins are welcome.
On the other hand, if you've had it with your good health, there are plenty of smoking rooms once you're through the international departures gate (4F) and on the domestic level (2F).
There is a Police office in Kansai airport, 2nd floor North Area. English, French, German, Spanish, Chinese, Korean and Japanese Sign Language are understood. 
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