In addition to the fixed-base lunar module simulators in Houston and at the Cape, astronauts also practiced at Langley Research Center on the suspended lunar landing trainer which was equipped with realistic surface views and lighting.
Perhaps the most significant point about the lunar-orbit flight proposed for Apollo 8 was that the command and service modules would fly the same route to the moon as would be used for the actual lunar landing.
General Samuel C. Phillips. Director of Apollo Manned Lunar Landing program
Dr. Wernher von Braun. The Rocket Man.
George Mueller Assoc. Admin. for NASA Office of Manned Space Flight