As of 10:15 a.m., the parking lots at the Dallas Zoo were completely full for the Zoo's semi-annual Dollar Day.
By the time the gates opened at 8 a.m. there were already more than 3,200 people waiting to get in, according to zoo officials.
That's more people than an entire day's zoo attendance on many mid-week days.
The record attendance for Dollar Days at the Dallas Zoo was more than 34,000 people.
Due to the crowds, traffic on I-35E was slowed around the Zoo area, while even more visitors try to get into the area.
The zoo recommends using the DART Red Line to head into the area in order to avoid the traffic and parking hassles.
Sean Greene, Deputy Director of the Dallas Zoo tells NBC 5 there are misting stations scattered throughout the park for people to cool off, as well as bottles of water available for $1 each.
NBC 5's Ben Russell contributed to this report.