BY AIR
Turkish Airlines (THY): THY, the national airlines of Turkey, has regular flights to Istanbul from principal capitals and major cities of the world. THY, Turkish Airlines offers flights to 155 world-class destinations with its fleet of 126 aircraft.
Please note that there are two international airports in Istanbul. Ataturk airport, bigger one, is in European side and most of the international flights are conducted through it. However, this airport is almost 70 kms away from Service Park.
Sabiha Gokcen Airport, that only 12 kilometers away from Service Park is in Asian side, newer but smaller than Ataturk Airport. However, THY will run scheduled international flights form Sabiha Gokcen as well, from 2009 Autumun onwards.
Please check out
http://www.thy.com/en-INT/index.aspx for detailed information.
Pegasus (PGS): Private airlines company Pegasus is also conducts international flights from 10 different countries to Sabiha Gokcen Airport. Please check out
http://www.flypgs.com/en/ for detailed information.
International Airlines: Most international airlines have regular flights from all major cities of the world to Turkey's international airports, especially to Istanbul.
BY SEA

Passenger Ferries: Apart from numerous passenger lines in the Mediterranean, several foreign shipping companies have regular car ferries from Venice, Ancona, Brindisi, Bari to the ports of Istanbul, Izmir, Cesme (Izmir) , Kusadasi, Marmaris and Antalya.
BY ROAD
Private Car: London-Istanbul, approximately 3,000 km.
Northern Route: Belgium, Germany, Austria, Hungary, Romania, Bulgaria and Turkey.
Southern Route: Belgium, Germany, Austria and Italy, with a ferry to Turkey.
Nationals of countries can enter Turkey with just a valid passport; not requiring a tourist visa. Also some countries which required a visa can obtain a sticker visa at the border.
How to reach Istanbul ?
Alternative 1: Via Yugoslavia and Bulgaria by road, entering through the Kapikule (Edirne) Customs, then by TEM (Trans European Motorway) to Istanbul.
Alternative 2: From Italy to Greece by ferryboat, then entering Turkey from the Ipsala Customs by road. Then from Ipsala, you can easily reach Istanbul by road.
Note for Highway Tickets

Although it is possible to pay highway ticket fees by cash in the toll plazas, it is not possible to do so while crossing the bridges over the Bosphorus in Istanbul. Therefore, our foreign guests are strongly advised to obtain a highway payment card, called KGS. The card is sold at the entrances of highways and the buyer should pay 30 Turkish Liras (app. 14 Euros) to obtain the card. However this fee will be loaded as credit into your card, so you can use it in the highways and bridges, during your stay in Turkey.
However, please note that it is not necessary to obtain a KGS card unless you cross the bridges over Bosphorus, since all course of Rally Of Turkey 2010 is on public roads which are toll free.