Best to purchase online. That way you have a specific timed entrance. At the door you take your chances with the time of your entrance. It could be a several hour wait.
Every guest over 2yrs is about $30... If you buy online it is about $25 per guest. https://philadelphia.legolanddiscoverycenter.com/tickets/
If you purchase the tickets online you save $5 so the tickets will be about 25 if you pay at the door I believe it's 30 per person
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