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Picnic Box - http://piknikbox.cz/ - if you only wish to grab a small bite, sandwich or fresh lemonade, you can do so in the Picnic box in the middle of the Park near the Moravian library.
Bistro PLAC - https://www.bistroplac.cz/poledni-nabidka/ - located 10 minutes away from the library is a Bistro where you can find a selection of sandwiches, salads, or pizza and soup according to the daily menu. Kotlářská 907/41
U Dřeváka - https://www.udrevaka.cz/denni-menu/ - located only 6 minutes away from the Library is restaurant and beer pub U Dřeváka - with menus consisting mainly of meat meals. However, there is always a vegetarian option available. Dřevařská 806/22
Grand restaurant Zelená Kočka - http://www.zelenakocka.cz/ - Only 5 minutes up the street from the Library, right next to the tram stop Klusáčkova, you can find a restaurant with the traditional Czech cuisine and a selection of Italian meals. Kounicova 57/83
Plzeňský dvur - http://www.plzenskydvur.cz/tydennimenu/ - The closest to the Library is a restaurant offering traditional Czech meals. Šumavská 542/29A
Taking about 6 minutes by walk to the Štefanikova street you may find various restaurants offering different cuisines, from traditional ones like Divá Bára http://www.restauracedivabara.cz/ or U Bíleho Beránka http://www.ubilehoberanka.cz/
, to more exotic Greek cuisine in Taverna Athena http://tavernaathena.cz/menu/, and several Korean, Vietnamese and Nepali restaurants.
Even wider selection of restaurants can be found on the Veveří street - traditional cuisine, several Vietnamese, Indian and Greek restaurants, burger restaurant the Immigrant https://www.theimmigrant.cz/burgers-and-beer. There is also Bistro Franz http://www.bistrofranz.cz/cs/obedove-menu-brno and Cattani http://www.cattani.cz/ famous for its homemade pasta.
The city centre - the Liberty Square and its surroundings are full of restaurants offering special lunch menus and selection of meals for dinner as well. Traditional Czech plates shall be found in Pegas restaurant and hotel, Varna, Stopkova Plzeňská Pivnice, Štatl http://statlbrno.cz/. The Czech tradition and world cuisine are combined in a NokNok restaurant http://www.noknokrestaurant.cz/ very near the centre of the Liberty Square. If you are searching for a less heavy meal, the Soul Bistro is located on Jezuitská 7 near the church https://www.facebook.com/pg/Soul-Bistro-233427320179534/photos/?ref=page_internal
Try also Ugova Salaterie - the salad restaurant situated in the centre part of the Liberty Square http://ugo.cz/ .
Near the Vegetable Market, you shall once again find somewhat traditional Czech restaurant and beer pubs like Potrefená Husa http://www.husabrno.cz/.
If you are searching for truly gourmet and delicious meals, then here is the selection of the best-rated restaurants in Brno:
Pavillon restaurant - Jezuitská 6 a restaurant offering unusual tastes and newest trends.
Borgo Agnese - Kopečná 43 offering a combination of traditional and unusual Italian meals https://www.borgoagnese.cz/cz/
Forhaus - Pekařská 4 - traditional food coming from Austro-Hungarian Empire with a modern twist.
Castellana Trattoria - Novobranská 4 - Restaurant offers homemade focaccias, prosciutto and pasta http://www.castellana.cz/
La Bouchee - Údolní 33 - offering light meals from French cuisine with extraordinary flavour combinations http://www.labouchee.cz/