The main attraction of Hradčany (Castle Quarter or Castle District) is the Prague Castle itself. However the Castle Quarter is much larger and is filled with many other attractions, palaces, churches and monasteries. Some of the palaces host excellent galleries, others are used as government or church buildings.
The Prague Castle (Pražský Hrad)  is the former seat of the King and is now the seat of the Czech president. This is Prague's number one tourist attraction so expect huge crowds and possibly long lines, especially during high tourist season. Your best bet is to come early, as soon as the castle opens.
Some of the areas require you to buy a ticket for entrance. You can buy one of two combined tickets as well. The short tour allows entrance to the Old Royal Palace, St. George's Basilica, Golden Lane and Daliborka Tower for 250 Kč. The long tour allows entry to all the same places as the short tour, as well as "The Story of Prague Castle" exhibition, the National Gallery display in the Convent of St. George, and the Prague Castle Picture Gallery all for 350 Kč. The entry to the St. Vithus Cathedral is free (but crowds are regulated) when the owned by the state, but money is charged when owned by the Catholic church. The legal battle over the ownership of the cathedral still continues.
Similar to other Royal Palaces, there is an hourly changing of the guard ceremony. At noon, the ceremony includes fanfare at a flag ceremony as well in the first courtyard.
St. Vitus Cathedral. In the center of the castle and the most important cathedral in all of the Czech republic. The oldest parts of the cathedral are from the 14th century, but the cathedral was not completed in the Medieval period. The highest tower was completed in Renaissance and Baroque styles much later, as is clearly obvious. The Western portal and both Western towers are even younger, completed in the 19th and early 20th centuries. However, the original Medieval plans were used for them and their relatively small age is not obvious. St. Vitus Cathedral was the place of royal coronations and also the location of the remains of several famous Czech Kings (notably Charles IV, of Charles Bridge fame). Go around the cathedral so you not only see the Western portal with the rose window and beautiful gargoyles, but also the original medieval Golden Portal in the south and the stunning Flying Buttresses in the east. Things not to miss inside the cathedral include the stained glass Rose Window in the west portal, the stained glass window by Alfons Mucha, the tomb of St. John of Nepomuk made of pure silver, the Royal Crypt underneath the cathedral (with the graves of Charles IV, his four wives, Wenceslas IV, Ladislas the Posthumous, George of Podebrady, Rudolf II, and Marie Amalie of Austria, the daughter of Maria Theresa of Austria) and the stunning St. Wenceslas Chapel with the relics of the saint and walls decorated with gold and more than 1300 gems. The Czech Coronation Jewels are kept behind the door with the seven locks (seven important people including the Czech President and the Czech Prime Minister keep the keys) in the St. Wenceslas Chapel. If you're willing to hike the 287 stairs to the top of the Bell Tower (the one with Baroque roof) you'll be rewarded with excellent views of the castle and the surrounding area. The Bell Tower holds Zikmund, the biggest bell in the Czech Republic.
Old Royal Palace(Starý královský palác). The original seat of Czech rulers. Visitors first enter the Vladislav hall, the largest high-Gothic vaulted space in Central Europe. Other rooms include the Palace chapel and throne room. At the end of the exhibit is "The Story of Prague Castle" exhibit, which features artificats from the castle's past.
St. George's Basilica. The 2nd oldest church in the castle and features a colorful Baroque facade. The interior is visibly older and is the burial place of the Premyslid family and the first Czech saint, Princess Ludmila.
St. George's Convent - National Gallery. One of several branches of the National Gallery is located inside this, the first convent in Bohemia. Today it houses the collection of Czech Mannerist and Baroque art.
The Golden Lane(Zlatá ulička). During the reign of Rudolf II, goldsmiths lived in a lively alleyway filled with tiny workshops, which were also their residence, hence it’s name. Tiny, cobblestoned walkway filled with brightly-painted little houses, where modern man has a hard time standing with the low ceiling. (It's tough to realize just how tiny our pre-20th-century ancestors were until you go somewhere like this). Franz Kafka occupied one of the houses for a short time, and this is why most people visit the Golden Lane. There really isn't another good reason unless you want to buy some overpriced souvenirs in the small shops now occupying the houses, or need to cut through the crowds to see the Daliborka.
The Daliborka. Built by Prince Vladislav in 1496, the tower at the far end of the castle is part of a new fortified wall. Its first prisoner was a recalcitrant knight named Dalibor who, according to legend, played his violin very sadly at the wall serenading the castle residents. Though, the thickness of the walls makes that legend a little unlikely. No one would have been able to hear him outside! Today the tower holds a small display of prison and torture techniques used during that time.
Prague Castle Picture Gallery(Královská zahrada). Housed in the original castle stables. It contains Renaissance and Baroque art, including parts of the original collection of Rudolph II.
The Royal Garden. To the east/north-east of the palace is a large park. Aside from its own beauty, it has an excellent view of the east bank of the river. Entrance is free.
The State Rooms at Prague Castle. Open to the public two days of the year, as they are mostly used exclusively by the President. Contact the Castle Information office for more details.
According to a legend, anybody who puts the St. Wenceslas Crown on his head unjustly will die violently within a year. It is said that the Reichsprotektor Reinhard Heydrich did just that. He was assassinated by Czech parachutists in less than a year.
Cafe Slavia, Narodni trida 1, Prague 1. A coffee tastes even better when accompanied by stunning views of the Vltava and Prague Castle. Cafe Slavia is the perfect place to stop for a coffee or light meal during a day of sightseeing in Castle.edit
Cafe Louvre, Narodni trida 20, Prague 1. Once frequented by Franz Kafka, this cafe is now a popular hotspot for a Prague locals. Their separate dining room offers french cuisine, for those looking for a different option than Czech food.edit
Lvi Dvur Restaurant, U Prasneho Mostu 6 Hradcany, Prague 1. Set in the back of Prague castle, the Lvi Dvur offers a truly unique dining experience. Traditional Czech cuisine is served in a room full of original period furnishings. Be sure to try the roast pig, the speciality of the house.edit
Barock, Parizska 21, 1st, ☎ 23 29 221. 8:30AM-1AM. This oh so trendy bar is filled with lithsome wannabe supermodels and cool hipster dudes that accompany them. It's the place to be seen, especially while nibbling on the Japanese snacks on offer.edit
Bar Bar, Vsehrdova 17, 1st, ☎ 57 31 22 46. With a young and hip clientele that has USA on its mind, Bar Bar serves tasty burgers, jumbo salads and American beers. The owner is Prince Antonin Kinsky, the scion of the ancient Czech dynansty, who can be found behind the bar.edit
Mecca, U pruhonu, ☎ 83 87 05 22. When the dance floor beckons, head to Mecca, which is the coolest of the cool clubs in Prague. Check out the bar that contains portholes and an aquarium and move to the latest beats straight from London.edit
EA Hotel Jeleni dvur, Jeleni 197, ☎ +420 233 028 333 (email@example.com), . checkin: 2:00PM; checkout: 12:00PM. All 30 rooms are equipped with TV/SAT, high speed Internet connection, direct dial telephone and safe deposit box. Public PC desk with Internet access and printer is available at the reception. Some rooms offer a wonderful view of the historical parts of Prague. There is a parking lot in front of the hotel for those coming by car.edit
Golden Well Hotel, U Zlate studne 166/4, 1st, ☎ 57 01 12 13, . Boutique hotel with one of the most beautiful views in Prague and restaurant terrace leading directly to Prague Castle.edit
Hotel Questenberk, Úvoz 15/155, ☎ +420 220 407 600, . Romantic, baroque-style, 17th century hotel. Each of the Single, Double, Deluxe Double rooms as well as the three Royal apartments are originally furnished and equipped with TV, WiFi, phone, safe, and minibar.(50°5'15.45N,14°23'27.008E)edit