In less than a week, Donald Trump, Ben Carson, Sen. Marco Rubio, and 11 other GOP presidential candidates will descend on Boulder for the party's third presidential nomination debate. Here's the info you need to know about the debate, including when it's over.

When is the GOP debate? 

Oct. 28. The first debate will start at 6 p.m. The main debate starts at 8 p.m. on the same day. 

Where is it? 

At the Coors Events Center on the University of Colorado Boulder campus. 

Can I get a ticket?

Probably not. There are no public tickets available and a very limited supply of student tickets. The university got 100 tickets to the main event, a fraction of the planned audience of 1,000. About half of the university's tickets will go to students, reports the New York Times

What is the debate supposed to be about?

The economy. Issues "such as jobs, taxes, the deficit and the health of the U.S. economy" will be topics for discussion, according to the university

Which candidates will be at the first debate? 

Louisiana Gov. Bobby Jindal, former Sen. Rick Santorum of Pennsylvania, former New York Gov. George Pataki; and Sen. Lindsey Graham.

Which candidates will be at the main debate? 

Donald Trump, Ben Carson, Sen. Marco Rubio, former Florida Gov. Jeb Bush, former Hewlett-Packard Chief Executive Carly Fiorina, Sen. Ted Cruz, former Arkansas Gov. Mike Huckabee, New Jersey Gov. Chris Christie, Ohio Gov. John Kasich and Sen. Rand Paul.

When will the debates be over? 

The debates are scheduled to conclude at 8 p.m. on Wednesday. CNBC ensured that after several candidates complained about the terms of the debate.  

What else is happening in Boulder during the debate? 

Different activist groups will stage events around the city. Latino leaders have planned a rally for 5 - 7 p.m. at Farrand Field on the CU campus. They hope to have 8,000 - 10,000 people at their gathering, reports the Daily Camera. Another group, Fossil Free CU, has organized a 5:30 p.m. march for civil engagement.

Why is the university hosting this event?

"We want to challenge our students and expose them to viewpoints they may agree or disagree with, because doing so sharpens their intellects and broadens their perspectives," explained the university on their Facebook page

The university has waived its normal rental fee of $15,000 for use of the 11,000-seat Coors Events Center basketball arena, reports USA Today

“We as an institution will get great branding and PR capacity, so we feel that it is a good investment,” university spokesman Ryan Huff the paper. 

What's the hashtag? 

If you're following along on Twitter, the official hashtag from CNBC is #CNBCGOPDebate. 

Editor's note: An earlier version of this story misstated the start times of the CNBC debates. The error has been corrected.