pack (someone or something) (in) like sardines
To fit many people or things very tightly or snugly into a small space. We didn't want to take more than one car, so Jeff packed us like sardines in his little sedan for the four-hour drive to Moab. Having a concert in our friends café was such a good idea! Sure, we had to pack people in like sardines, but everyone had a great time. I wish you would just let us buy you a bigger backpack! It makes my own back hurt watching you pack those books like sardines into your little shoulder bag.
pack someone or something (in) like sardines
Fig. to squeeze in as many people or things as possible. (From the way that many sardines are packed into a can.) They packed us in like sardines. There was no room to breathe. They packed in the people like sardines. Dave got a box and packed old negatives in like sardines.