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Thirteenth Algorithmic Number Theory Symposium ANTS-XIII
University of Wisconsin, Madison
July 16 – 20, 2018

Thirteenth Algorithmic Number Theory Symposium (ANTS-XIII)
July 16 – 20, 2018

Travel and transport

The symposium takes place at the University of Wisconsin, Madison.

Getting to Madison

O'Hare Airport in Chicago is the closest major international airport (airport code ORD) and there are shuttles from Chicago to Madison. Midway Airport (airport code MDW) may serve best for domestic flights to Chicago, and Madison does have a small airport, Dane County Regional Airport (airport code MSN) with flights from a number of major US cities. Milwaukee's General Mitchell International Airport (airport code MKE) is another option.

Van Galder Bus Line has regularly scheduled trips to Madison from O'Hare Airport (most international flights arrive in Terminal 5) and Midway Aiport. Or if you would like to visit Chicago for a couple days before or after the conference, there is also bus service from Chicago's Union Station (downtown Chicago). The trip to Madison is a little over 3 hours, and the buses are equipped with Wi-Fi and USB charging ports. The bus drops off and picks up at Langdon and Park in Madison (the University Memorial Union). This is approximately two blocks north of Grainger Hall.

If you fly into Madison, trips from the airport to Grainger Hall with Union Cab cost about $25. Allow for 30 minutes in transit. Their phone number is 1-608-242-2000. Alternatively, you can take the bus to the university, but you will need to transfer from bus #20 at North Transfer Point, to bus #2. See the next section for information on the bus system.

If you fly into Milwaukee, you can take Badger Bus to Madison (drop off at the same place as Van Galder Bus Line above). The trip is $23 one way if purchased online and is about 2 hours in duration.

Getting around Madison

The area around Grainger Hall is generally walkable. Madison does have an extensive bus system. Suggested routes from each of the hotels is in the hotel section of the Local info tab. Adult fare is $2 each way, $5 for a day pass (available on the bus), or $17.25 for a 10-ride card (available by mail, but allow 10 business days for mailing, or at at University Bookstore, 711 State Street). Be sure to have exact fare as they do not make change on the bus. Youth and Disabled/Senior discounts are available. There are several apps to help you navigate the system listed at:

Parking on campus

There is a parking garage at Grainger Hall. Daytime rates: $1 per 30 minutes for the first 2 hours, $1 per hour thereafter, $12 maximum per day. 4:30 pm-midnight: $1 per hour, $5 maximum per evening. “Value permits” for $12/day are available at Please allow at least two weeks for processing.

The closest city lot to Grainger Hall is State Street Campus Garage (if you want to sound like a local, call it "Lake Street Ramp") with entrances at 415 N. Lake St. and 400 N. Frances St. The next closest lot is Overture Center Garage, 318 W. Mifflin St. More information on city-run parking is at

Visa requirements

You are responsible for making your own visa arrangements to enter the United States. Travelers from many countries do not need a visa to enter the US for a short trip; however, such travelers must still fill out an electronic preauthorization before traveling. Below are some links that may be helpful.

Other notes

When traveling to the US, you must clear immigration and customs at your point of arrival in the US. If you have a connecting flight in the United States, checked baggage will have to be claimed before customs and rechecked immediately afterwards. (Exception: if you enter the US via a flight from Canada, you will clear US immigration and customs at your departure airport in Canada.)

Chicago and Madison are both in the Central time zone. During summer, this is 5 hours behind GMT.

© 2017-2018 Jennifer Paulhus (with thanks to Kiran S. Kedlaya, and by extension Pierrick Gaudry and Emmanuel Thomé)