The venue for the workshop is Geneva Observatory in Versoix, which can be reached by public transport. It is not in central Geneva. The "Observatoire de Genève" bus stop is a few minutes walk away from the main building of Geneva Observatory, we will be using the Astrotec meeting room on the second floor.
The Lake Geneva hotel is in downtown Versoix very close to the train station, Versoix Gare. There is a direct bus between the airport and Versoix Gare (bus number 50) and a different direct bus between Versoix Gare and Geneva Observatory (bus number 55). The total travel time from Geneva airport to the observatory is a little over one hour using these buses. It is sometimes faster to take a train from Geneva airport to Versoix Gare via Geneva train station, while adding an extra connection, and of course a taxi is the fastest and most expensive option. Some more details below.
Transport from Geneva airport to Lake Geneva hotel / Versoix Gare
There are many ways to reach Versoix Gare from Geneva airport by public transport, either by train or by bus. Conveniently, the number 50* bus from Geneva airport (direction "Versoix Centre Sportif") stops at Versoix Gare. At the airport you should buy a "Billets Tout Genève - zone 10" for 3 CHF, you can pay by credit card as well as cash.
Geneva airport bus stops and train station (Bus 50 leaves from area "B")
Geneva Airport to Lake Geneva hotel / Versoix Gare
*Note that there is an equivalent but much less frequent bus number 54 (going in direction "Versoix Centre Sportif"), depending on what time you arrive, also leaving from area "B".
Train
To take the train to Versoix Gare, the Geneva airport train station is shown on this map. Take a train to "Genève" (Geneva central train station, also called Gare Cornavin) and change there to any train stopping at "Versoix".
Transport from Versoix Gare to Geneva Observatory
Bus number 55 goes directly between Versoix Gare and Observatoire de Genève every 30 minutes. Take the bus in direction "Chavannes des Bois" from Versoix Gare to go to the observatory, and in direction "Bossy" to go from the observatory to Versoix Gare.
Lake Geneva hotel to Geneva Observatory
Free Public Transport ticket at Lake Geneva hotel
If you ask at check-in, you should be able to obtain a free pass for public transport for the duration of your stay at the hotel. This is very common and may apply at other hotels but YMMV - ask !
Taxi
A taxi can take you from Geneva airport directly the observatory in 15-20 minutes depending on traffic and should cost around 80 CHF.
