The Petřiny bus a tram stops are ones the nearest to the Institute. Their position is described in the commented photo.

Tips for your orientation, if you never have been in Prague:
The stops of trams and city buses are marked by bollards of
red and yellow colour with a symbol of tram (bus) in black, white
and blue. They are equipped with tables carrying a name of the
stop and line numbers. The stops are standardly equipped by time
tables of proper lines; time tables contain departures from the
stop, list of stops of the line with times to get there.
The direction is indicated on the front of bus/tram.
For more general information about Prague City Transport in
English language, see Prague
Information Service or Prague
Public Transit Company.
About this text:
The simplest variant is usually presented, although it need not be necesarilly the shortest one. Additional variants of described ways and ways from another places are described in a separate document.
You are also encouraged to use the online time table to find the best way - open http://www.dpp.cz/en/journey-planner/ and enter Petřiny into "to" field. If you plan to come into Prague by train or coach, we suggest to use the combined http://jizdnirady.idnes.cz/vlakyautobusymhd/spojeni/ , fill in "Petřiny" into "To" field and choose "Stops (Prague)" in "Category" field in the same line, whereas your city into "From" field and "Cities and villages" or "Stations (train)". The programme suggests you the most suitable station for changing to city transport.
Take bus 179 (see a map of the airport). In the peak hours, the bus leaves every 12-20 min, outside peak hours and on weekends every 30 min. Get off at the Petřiny stop (14th stop from Terminal 1, 13th from Terminal 2; 8km, 19-23 min), then walk 100 m back. An Institute building is located behind the tram terminus. (see a map or commented photo)
Take tram 26 (direction of Liboc, Divoka Sarka) to the 8th
stop - Hradčanská (4 km, 13-15 min ), (see a map)
change for tram 1 or 18 to Petřiny (terminus, 5
km, 13 min)
Take the Metro, the yellow line B (direction of Zličín) to
Nove Butovice station (3 stops; 8 min), (see a map)
then use bus line 179
to 11th stop - Petřiny (7 km, 14-18 min). The stop of bus 179 is
located directly in front of the Institute. Before the stop, the
bus passes a tram terminus, what can help you to recognize the
correct stop to get out.
Take the Metro, line A (direction Dejvicka) to Hradcanska
station (8 stops, 14 min)
and change for tram line 1, 18 to Petřiny (last stop, 5
km, 13 min).
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