Wikipedia says, “In Europe packrafts are used together with train travel.”
That is not true, packrafts are not used in Europe a lot at all 
However, what has been stated, has to be, so I gave it a go on the bank of the river Kwisa
between the towns of Zebrzydowa and Zagan by “Zug” (german for train), so I call this trip “Tripple Z”:
http://picasaweb.google.de/sven.schellin/GrenzeDerOberlausitz#
It is a 2-3 day trip in south western Poland on 60-70 km fast flowing water only navigable in spring (at min. 5 m^3/s, a little less for packrafts, we had 8). One rapid (class 2), a few weirs (dangerous at high water), some destroyed weirs (navigable) and kilometres of sweet shallow running water over gravel ground, meandering through unmaintained forest and swamp, along original small villages and relicts of older times (abandonened places and destroyed bridges). Quite an exception for middle Europe and central Poland in particular. However, due to the sensitivity of the water level and the limited time frame, it is not very popular for canoeing. So this is where packrafts excel. Clear recommendation.
Water level: http://www.pogodynka.pl/hydro.php
Additional information: http://rivers.raft.cz/polsko/kwisa.aspx?ID_reky=240
Weather forecast: http://wetterstationen.meteomedia.de/messnetz/forecast/094990.html
Train scheduals: http://reiseauskunft.bahn.de/bin/query.exe/dn?ld=96139&seqnr=3&ident=ix.05573139.1271771126&rt=1&rememberSortType=minDeparture&REQ0HafasScrollDir=1
Despite some maps indicating a train line directly along the river, there is no such thing in reality. The towns of Zebrzydowa and Zagan are the only ones with train access/stations along that part of the river.
