INDYCAR announced today that the Grand Prix of Houston will not be returning to the Verizon IndyCar Series schedule in 2015.

The 1.7-mile temporary circuit at NRG Park hosted doubleheader races in each of the past two seasons, but INDYCAR and officials from the Grand Prix of Houston were unable to define a workable date for the 2015 event.

“INDYCAR is thankful to Mike Lanigan and his team for all their hard work and for the tremendous support of the Grand Prix of Houston that we received from Shell, Pennzoil and Honda,” said Mark Miles, CEO of Hulman & Co., the parent of INDYCAR and the Indianapolis Motor Speedway. “We look forward to a continued relationship with Mi-Jack Promotions and will always keep our options open when it comes to an important market like Houston.”

The Grand Prix of Houston was previously part of the Indy car schedule from 1998-2001 and 2006-07.