There are direct flights to Warsaw from major European destinations, and Ryanair flies from London Stansted to eight regional Polish cities (Rzeszow, Krakow, Lodz, Wroclaw, Poznan, Gdansk, Bydgoszcz and Szczecin). Flights to Warsaw also depart from US cities such as New York and Chicago, which have large Polish communities. There is no departure tax. Train and bus fares from some European destinations can be as expensive as discounted air fares, unless you have some kind of transport pass. Road connections with Poland are good and getting better, but there are still border delays, especially when crossing from other Eastern European countries. There are sea connections from Denmark and Sweden to Gdańsk, Gdynia and Świnoujście. All services have car-freighting facilities.
There is a comprehensive network of domestic air routes. All flights between regional cities travel via Warsaw, and connections aren't always convenient. There are attractive standby fares for young people and promotional fares on selected flights in certain periods that are available to everybody. The trains are pretty good and where they don't go the buses do. As well as the plodding government service, private bus companies undercut each other viciously on many intercity routes. Driving your own vehicle around Poland is by far the most convenient option, but don't bring your spiffing new Jaguar, even if you forewent the walnut trim: it's gonna get ripped off. Fill up your tank every time you see a petrol station and carry some spare mechanical bits and pieces, otherwise you'll be waiting around for a couple of weeks for them to arrive from Germany. Rural Poland, being mostly flat and relatively quiet, is quite conducive to cycle touring, but the urban areas are bike-unfriendly, with few dedicated paths and many hostile motorists.