Travel
How to reach Leiden and the Leiden Observatory
Note: this is NOT the old Observatory ("Sterrewacht") located in the center of town
Leiden Observatory is located on the fourth and fifth floor of the Oort and Huygens buildings, which are connected by a glass corridor. The Oort building also houses the Lorentz Center for hosting international workshops on the third floor. For directions to Leiden Observatory follow the directions to the Lorentz Center which can be found here. Maps of Leiden city and the location of the university buildings can be found here.
Accommodation
Hotels: http://portal.leiden.nl/en/tourism_leisure/staying_overnight/hotels
B&Bs: http://portal.leiden.nl/en/tourism_leisure/staying_overnight/bed_breakfasts
AirBnB: https://www.airbnb.com/s/Leiden--Netherlands
Some suggestions
Hotel Ibis: http://www.ibis.com/nl/hotel-8087-ibis-leiden-centre/index.shtml
Hotel Golden Tulip:http://www.goldentulipleidencentre.nl/en
Close to the observatory (but 30 min walk to the city centre): Hotel Garden Inn Hilton: http://hiltongardeninn3.hilton.com/en/hotels/netherlands/hilton-garden-inn-leiden-AMSLNGI/index.html
If you are looking for a Hotel in the historical/city centre we recommend
http://www.residence102.com/ (45 min walk to Leiden Observatory)
http://www.huysvanleyden.nl/ (45 min walk to Leiden Observatory)