VANCOUVER - Several thousand people attending a full dress rehearsal of the 2010 Olympic Opening Ceremony are managing to keep mostly mum about what they saw inside - but what they went through to get there is another story.

The dress rehearsal was held Monday night at B.C. Place Stadium, where the Opening Ceremony will be held on Friday night.

Audience members appear to be honouring Olympic pleas not to reveal any production secrets.

However, the dress rehearsal was also a dry-run for security measures to enter the 60,000-seat venue, and participants say those measures were an eye-opener.

With the stadium estimated at only about one-third full, one man says it took at least an hour to make it through snaking line-ups to clear airport-style security checks.

He says anyone carrying any sort of bag or purse was directed to an even slower line, echoing warnings from Olympic organizers that ticket holders to the opening and closing ceremonies should be prepared for waits of up to four hours to get in.