Paolini, in his first public reading of Brisingr, at the Union Square Barnes & Noble in New York City. Photo: Lisa Berg.

Brisingr (Knopf), the long-awaited third volume in Christopher Paolini’s Inheritance cycle, arrived last Friday night, September 20, at midnight. In a record for Random House Children’s Books, the book sold 550,000 copies in its first day.

Random had printed 2.5 million copies of Brisingr, the largest-ever first printing for the division. First-day sales for the title were four times that of Eldest, second in the cycle, which pubbed in August 2005. RHCB president Chip Gibson said the numbers for Brisingr “far surpassed our projections.” More than 2,500 bookstores held midnight parties.

Random House U.K., which published the novel simultaneously, reported first-day sales of more than 45,000 copies, “Brisingr is by far and away the fastest-selling book we’ve ever published,” said children’s sales director Helen R andles. The company also called it the fastest-selling children’s book in Britain this year.

In addition to midnight parties held at bookstores, many libraries joined in the fun as well. The Norwich Public Library in Norwich, Vt., hosted a read-a-thon last Friday night for fourth- to eighth-graders, to celebrate the release of Brisingr. At midnight, the kids received their pre-ordered copies from Norwich Bookstore across the street, and got to stay up all night at the library, reading. Photo: John Langeloh.

Paolini is currently on a 10-city book tour. In all editions, the first two volumes have sold over 15.5 million copies worldwide. A fourth volume will conclude the Inheritance cycle, though a publication date has not been set.

Eagerly anticipated additions to big children’s series have been arriving with record-breaking numbers of late. Last month, Little, Brown sold 1.3 million copies of Stephenie Meyer’s Breaking Dawn on its first day of publication. And the record that may never be broken: the final Harry Potter volume, Harry Potter and the Deathly Hallows, sold 8.3 million copies in its first 24 hours in July 2007.