Julia and Winston first meet at the government agency where they both work, the Ministry of Truth. As they start to get interested in each other, the two of them meet privately in a wooded area. After they start their affair, they rent a room over a junk shop and meet there frequently. At the novel’s end, after Winston has been tortured and learns to love Big Brother, he and Julia meet in a park for one last encounter.

Although Winston had seen a dark-haired woman around the ministry, he did not know her name and was suspicious of her intentions. Winston had started committing forbidden acts, such as keeping a diary and thinking bad thoughts about the government. As he becomes increasingly concerned about spies, he suspects that Julia may be one. His anxiety increases when he sees her near the secondhand shop he frequents.

Despite his misgivings, Winston becomes intrigued and dreams about having sex with her. At work, she fakes an accident so she can pass him an unsigned love note. Soon afterward, they meet privately outside of work, in a wooded area outside the city. This meeting includes their initial sexual encounter, and they embark on an affair.

Winston rents a room for them to meet in, located above the same junk shop. On one occasion, they both meet with O’Brien at his apartment, where they are fooled by his ruse of opposing the government.

It later develops that their meeting room had a hidden camera. After both of them are arrested, they do not see each other during the period they are detained. Breaking under torture, Winston betrays her. Once he is released, he is also retired from work. They schedule and hold a brief meeting in a park and learn that each betrayed the other.

Long before they embark on their ill-fated sexual affair, Winston and Julia are aware of one another at their job. They both work at the Ministry of Truth: Winston is a clerk in the records department, and Julia works in fiction.

Winston initially despises Julia on two fronts. Firstly, he thinks she is scrutinizing him for any possible disloyalty. He assumes she is zealously devoted to the Party and fears his own rebellious thoughts being sniffed out by her. Secondly, he is sexually attracted to her but believes she is unavailable due to her membership in the Junior Anti-Sex League, an organization that promotes celibacy in the name of the state. This makes Julia a forbidden fruit as well as a symbol of everything the sexually frustrated Winston hates about his society, which looks down on sex as anything other than a procreative method to create more citizens. As a result, he engages in several violent erotic fantasies about her.

However, Julia is not what she appears. She is also disloyal to the Party and avidly pursues sexual relationships despite her public image as a dedicated celibate. She ends up reaching out to Winston by passing him a love note while at work, instigating their doomed romance.

Winston and Julia meet at the Ministry of Truth or Minitrue, where they both work. They keep eyeing each other obliquely. Winston doesn't know her name, but calls her the "dark-haired girl." He thinks she is spying on him, because he has noticed her glancing at him. He especially believes this after he sees her on the street near Mr. Charrington's shop. 

They make contact when, outside a lavatory at work, Julia pretends to fall down. Winston helps her up and she slips a note saying "I love you" into his hand, all right in front of a viewscreen.

They meet in a wooded area outside the city. It is not until this point that Winston learns her name is Julia. He tells her his prior feelings:

'I hated the sight of you,' he said. 'I wanted to rape you and then murder you afterwards. Two weeks ago I thought seriously of smashing your head in with a cobblestone. If you really want to know, I imagined that you had something to do with the Thought Police.'

Julia is delighted that her "front" of a good Party member is working so well (she thinks), but the passage is important. At this point, Winston is still more or less dehumanized and sexually frustrated, filled with fearful and aggressive feelings--in other words, just the way the Party wants him to be. Now that he has met up with Julia, that will change. 

Julia and Winston meet at the Ministry of Truth where they both work. Winston recognizes Julia as the dark haired girl whom he thinks is spying on him and works in the Fiction department. They keep seeing each other and occasionally exchange glances but never speak until one day when they meet along the corridor and the dark haired girl stumbled and fell. Winston helped her up and they parted ways after she slipped him a note reading “I love you” in his hand. They manage to whisper to each other at the canteen during lunch and agree to meet at Victory Square where they arrange their first meeting away from the crowd in the woods. It was during this meeting that the dark haired girl formally introduced herself as Julia. She already knew Winston’s name. After this, they continued to meet in different places but for less than thirty minutes each time, they took precaution. Eventually, they used the room on top of Mr. Charrington’s junk shop until their arrest.

Winston and Julia have noticed each other for a long time.  He watches her and secretly hates her and all she stands for as a loyal Party member during the Two Minutes' Hate.  She watches him and tags him as someone who is not loyal.  Both admit to the other later what he/she thought of each other, which should have made them more careful.

Their first actual encounter came after the Two Minutes' Hate when Julia "runs" into Winston and falls down.  When he helps her up during the seemingly innocent connection, he realizes she has slipped a note into his hand.  When he is able to open it in private, he reads, "I love you".

Later, they plan to meet in a secret place--the wooded area in the park--away from microphones and cameras where they are intimate for the first time.  They continue planning clandestine meetings until they are able to secure an apartment where they escape the Party (or so it seems) to enjoy each other and life as the Proles do.

In 1984, where do Winston and Julia meet? Why? 

In 1984, it is impossible for Winston and Julia to be seen together in public because their relationship is not sanctioned by the party. In fact, the party actively encourages people to become celibate and is, as Winston comments, "actively trying to kill the sex instinct." (Part 1, Chapter 6). The party does, however, condone marriage, though strictly for the purposes of procreation, though does not allow people to choose their own marriage partner. This is a decision for a specially-selected committee. Anybody who contravenes these rules and regulations attracts the attention of the Thought Police and the very real possibility of going to Room 101 or, even worse, being vaporised.

For Winston and Julia, then, being discrete is of paramount importance. Their first meeting takes place in the busy Victory Square (Part 2, Chapter 1) but the fear of being detected is overwhelming. From then on, they meet in places which are far away from telescreens and prying eyes. As such, future meeting places include the woods, an abandoned church, and, finally, in a rented room above Mr Charrington's shop. 

While they cannot avoid the Thought Police forever, this cautionary behaviour enabled their relationship to thrive and drives the plot to its grand, yet tragic, conclusion.

Where do Julia and Winston set up their rendezvous in 1984?This question comes from part two in the book.

In Part Two, Chapter One, Julia manages to slip Winston a note saying that she loves him. After receiving the note, Winston tries several times to speak to Julia in the canteen during lunch but is unable to have a brief conversation with her until a week passes. Winston eventually manages to sit down across from Julia in the canteen, where they plan to meet in the crowded Victory Square after work to further discuss their plans to see each other. Later that evening Winston and Julia meet in Victory Square, where the masses gather to jeer at a convoy of Eurasian prisoners of war. In the crowded area, as the truck of enemy soldiers passes, Julia stands next to Winston and gives him directions to a secluded spot in the country to meet her that Sunday. On the first day of May, Winston takes a train to the countryside to meet Julia in a tranquil pasture that reminds him of the Golden Country he dreams about.

Where do Julia and Winston set up their rendezvous in 1984?This question comes from part two in the book.

In Part Two of this book, Julia and Winston meet a number of times in the course of their affair.  I am going to assume that you are asking about the first time they meet and have sex with each other.

This rendevous is set up for a secluded area out in the country.  We are not told where it is -- like what town it is near or anything.  Julia has been there before, but Winston has not, except in his dreams.  She tells him exactly how to get there, what train to take, which way to turn going out of the station, how far to go, etc.