Poland is a deceptively large country, so it's best to scale down your geographic ambitions from the outset. One week in Poland is ideal if your goal is to get in two big cities -- say, Warsaw and Kraków -- and a little bit in between. For anything more comprehensive, give yourself 10 days or, ideally, 2 weeks.
The problem isn't so much Poland's size, but the transportation infrastructure. Train travel in Poland continues to improve, and an express train can now get you from Warsaw to Kraków in around 3 hours, but most trains still move aggravatingly slowly, and you can literally spend a whole day on the train going from, say, Kraków to Gdansk or from Lublin to Wrocaw. Bus travel is similar; buses can travel only as fast as the roads allow. That said, buses are often a better bet than trains for travel within regions and along selected city-to-city routes.
And then there are the roads. Poland's antiquated network of two-lane highways is the butt of national jokes and a real bottleneck to the country's economic growth. The country has launched a massive road-building effort funded by the European Union, but for the foreseeable future (certainly the lifetime of this guidek), be prepared to put up with huge traffic jams, crowded and impassable roads, and frustrating detours that always seem to pop up just as you approach your destination. As a rule of thumb, figure on 2 hours of car travel for every 100km (62 miles). One notable exception is the excellent A4 superhighway (autobahn might be a more apt term, given the speeds people drive), linking Kraków with the German border in the west and passing through Katowice and Wrocaw along the way. The EU's involvement has a darkly comic dimension. Invariably, when you see a sign saying something like "This road brought to you by the European Union," expect to find traffic backed up for miles in both directions ("This traffic jam brought to you by the EU," might be more appropriate). Even with the hassles and inconveniences, car travel might still be the best way to explore smaller towns and off-the-beaten-track destinations otherwise accessible only by sporadic bus service.
Depending on the length of your stay, there are several ways you could focus your itinerary to get the most out of your trip. One logical choice is to divide the country into north and south, including Warsaw in both, but making Gdansk (north) or Kraków (south) the focal point of your travel. Another way would be to focus on a particular interest -- World War II or Jewish heritage, for example -- or on an activity such as hiking, biking, boating, or, yes, even sunbathing on the beach.
Note: This information was accurate when it was published, but can change without notice. Please be sure to confirm all rates and details directly with the companies in question before planning your trip.