Before Penny moved out of her place to live with Leonard in apartment 4B, she called apartment 4A home for years. It was the home that gave her independence and introduced her to her future husband and best friends on The Big Bang Theory.

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While Sheldon and Leonard’s apartment was the main spot to hangout, Penny’s place saw just as many hilarious and heartwarming scenes. Penny hosted girls' nights, Sheldon stopped over to talk to her when Leonard was bothering him, and Leonard spent more time there than anyone because he always loved her. Penny’s apartment saw a bunch of fantastic moments on The Big Bang Theory

When Leonard Proposed For Real

Leonard proposes to Penny on The Big Bang Theory

It’s an ongoing joke in the series that Leonard and Penny break up a lot, and that Leonard proposes a lot. However, there’s one proposal that counts as the “real” proposal and that happened in Penny’s apartment. 

After a hard week of realizing she was awful at acting, she turned her thoughts on the people she was thankful for. More than ever, she was grateful for Leonard and noted that he was the one thing she could rely on. Leonard assumed that Penny was basing her feelings for him on her sadness but the conversation ended in an engagement. After calling Leonard a “stupid Pop-Tart,” he dropped down on one knee and proposed to her.

Penny Blossoms 

Sheldon Cooper and Penny make Penny Blossoms in The Big Bang Theory

When Sheldon visits Penny’s apartment, he finds her making something she called Penny Blossoms. They were small flower clips for people's hair. Sheldon realized that Penny couldn’t start a business without his help, so he showed her how to create a proper assembly line.

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The two were doing such a great job with their Penny Blossom creations that the others jumped in to help. Seeing her and Sheldon learn from each other and help each other is one of the best aspects of their friendship. 

Penny & Sheldon Puzzle Debacle

Penny and Sheldon doing a puzzle on The Big Bang Theory

When Raj creates a spontaneous scavenger hunt, no one is thrilled to work with Penny because she wasn’t going to be a big help. Hilariously, it was Sheldon who got paired with her, and the two headed to her apartment to work on the first clue: a puzzle. 

After connecting a few puzzle pieces, Penny knew that the place they had to visit was the comic book store. Sheldon, however, refused to go to the comic book store until the entire puzzle was complete. Penny was jumping around her apartment ready to go to the comic book store but had to wait for Sheldon to give her the go-ahead. 

Penny Teaches Sheldon How To Act

PENNY ON THE PHONE WITH SHELDONS MOM - TBBT

When Sheldon begins teaching at Caltech, he reaches out to Penny on how to become more personable in front of a group of people. As an actress, Penny felt like she had the skills to loosen Sheldon up.

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While at Penny’s apartment, Penny gives Sheldon a series of improv lessons that don’t go as planned. Sheldon was too literal and didn’t know how to go with the flow. However, when the two improvise a scene regarding Spock and a young Sheldon, it becomes all too real for Sheldon. He starts crying at the thought of leaving his mother for space. Penny knows the lesson failed, so she called Sheldon’s mom and told her she “broke” her son.

An Embarrassing Girls' Night

Bernadette smiling while competing for Miss California Quiznos 1990

In “The Troll Manifestation,” Penny, Amy, and Bernadette are at Penny’s apartment having girls' night. After boredom kicks in, they decide to liven up the evening by bringing up past embarrassments.

They found Penny’s movie, Serial Apeist, and watched it in disgust. They even found old footage of Bernadette singing Spice Girls during a beauty competition. But one of the most intriguing embarrassing parts was a Little House on the Prairie fan-fiction story Amy wrote based on a futuristic version of her and Sheldon. All the ladies took turns reading the passages and it was oddly moving. Penny and Bernadette didn’t want the story to end and were upset when the guys barged in and interrupted their storytime.

Amy’s Oil Painting

Amy shows Penny her commissioned oil painting of them

In "The Rothman Disintegration," Amy wanted to do something nice for Penny to show her how much their friendship means to her. During a girls' night with Bernadette, Amy barged in with a massive painting of the two of them. Penny’s look of confusion perfectly matched her expression in the painting. It was not a small token of appreciation Penny could hang on the wall; the portrait was massive.

Penny took the painting down as soon as Amy left, but when Amy popped her head back in to borrow a DVD, she found out Penny’s true feelings for the painting.

When Sheldon And Leonard Broke Into Her Apartment To Clean

Sheldon Cleaning Penny's Apartment in the dark on TBBT

When Penny first moved into her apartment and got to know Leonard and Sheldon on a friendly level, Sheldon couldn’t sleep knowing how messy her apartment was. That unorganized mess was far too close to his space.

One night when everyone was sleeping, Sheldon used the spare key that Penny lent him and he sneaked into her apartment to clean. Leonard woke up in the middle of the night and caught Sheldon going through Penny’s things but there wasn’t much he could do. Penny’s apartment was unkempt. When Penny woke up the next morning and saw that someone went through her home while she was sleeping, she freaked out. She immediately knew it was Sheldon and Leonard and gave them a stern talking-to.

Her New Gaming Obsession

A dirty and disheveled Penny playing a video game

When Penny learned how to play Age of Conan, she found it more enjoyable than she expected. With Sheldon’s help, she was getting better and better. Her fondness for the game impressed Sheldon, but everyone else realized that Penny was becoming obsessed.

After waking up Sheldon in the middle of the night for help and missing work just to play the game, Penny became a monster. She didn’t shower, she didn’t change her clothes, and she spent every waking moment in her apartment playing this game. And just when it seemed like nothing would snap her out of this spell, Penny realized she was in over her head when she agreed to hang out with Howard’s character. Virtually dating Howard was enough to snap her out of it.

Sheldon And Penny's Version Of Intimacy

sheldon and penny looking into each others eyes - tbbt

When Amy read a study where two people can fall in love in a short amount of time by spending one-on-one alone time together and asking each other questions, Sheldon decided to give it a whirl. Instead of asking a stranger to be his partner, he and Penny tried it in her apartment while Amy and Leonard visited an escape room with Raj and Emily.

While at Penny’s apartment, the two sat close to each other and asked personal questions to get a better understanding of one another. To finalize the study, they sat in silence and looked into each other’s eyes for a couple of minutes. The two friends got emotional while looking into each other’s eyes as they realized they meant more to each other than they could comprehend. By the end of the study, they weren’t in love but they did love each other.

Where Are Your Adhesive Ducks, Penny?

Sheldon drives Penny to the hospital on TBBT

With Leonard away, Sheldon and Penny planned on having a quiet night to themselves in their respective apartments. But when Sheldon heard Penny screaming for help, he jumped into superhero mode and saved the day. He let himself into her apartment (after knocking three times) and found Penny wrapped up in her shower curtain after taking a spill in the shower. She dislocated her shoulder and needed help getting to the hospital. Sheldon immediately scolded her for not having adhesive ducks on the bottom of her tub to prevent falling. Even funnier, he had to dress Penny. As she sat on the bed, he blindly picked out an outfit for her and helped dress her. The entire scene was so awkward that it was hilarious.

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