direction South - from Błonie - public (P.PKS) and private buses - 15 minutes (from Grodzisk Mazowiecki - 35 minutes)
direction West - from Kampinos - P.PKS - public buses - 15 minutes (from Sochaczew - 50 minutes)
direction North - from Nowy Dwór Mazowiecki - P.PKS - public buses - 45 minutes (from Płock - around 3 hours)
train + bus:
From the train station Warszawa Wschodnia, Warszawa Śródmiescie lub Warszawa Zachodnia with a train to the station in Błonie, and from Błonie you must take a bus directly to Leszno. Timetables of Polish State Railways are avialable on the site www.pkp.pl(also in English), and timetables of buses from Błonie to Leszno available here
a bicycle:
There is a Bicycle Route which starts in Warsaw at Chomiczówka (East part of Warsaw) and it goes through: