Rzeszów is a city in southeastern Poland.
To Ukraine you can't cross the border by foot in Korczowa, but in Medyka! In Korczowa you can wait for 3 hours because there are a lot of cars
North towards Lublin (N19)
Take a bus that goes north along the street Lubelska and hitch from a bus stop at the north edge of the city.
South to Slovakia (N9)
Take bus 28 south out of the center. Get off at the stop after the large Praktiker store. You can hitch south straight from the bus stop. In summertime, much of the traffic is staying inside of Poland, so a combination of rides may be necessary to reach the Slovak border.