Grab (Serbian: Граб) is a village in the municipality of Trebinje, Bosnia and Herzegovina.

Coordinates: 42°36′16″N 18°25′34″E / 42.60444°N 18.42611°E / 42.60444; 18.42611

Trebinje (Serbian Cyrillic: Требиње, Serbian pronunciation: [trɛ̌biɲɛ]) is the southernmost municipality and town in Bosnia and Herzegovina. It is administratively part of the Republika Srpska entity and is located in southeastern Herzegovina, some 10 km (6.2 mi) from the Adriatic Sea. The town was first mentioned in the 10th century.

The town lies in the Trebišnjica River valley in southeastern Herzegovina, some 24 km (15 mi) by road from Dubrovnik, Croatia, on the Adriatic coast. There are several mills along the river, as well as several bridges, including two in the town of Trebinje itself, as well as a historic Ottoman Arslanagic bridge nearby. The river is heavily exploited for hydro-electric energy. After it passes through the Popovo Polje area southwest of the town, the river - which always floods in the winter - naturally runs underground to the Adriatic, near Dubrovnik.

Trebinje has a sub-tropical, Mediterranean climate with short mild winters and long blazing summers. Trebinje is now the warmest city in the Republika Srpska and Bosnia and Herzegovina. The average annual temperature in the city is 16.6 ° C (2011) and the average January temperature is 7.5 °C, while the July temperature is 26.5 °C. Snow is very rare. In the summer, temperatures at day are around 40 °C and in winter the temperature rarely drops below 0 °C. The highest recorded temperature was 45.5 °C on 22 July 2007. And the lowest recorded temperature was -8.6 °C on 17 January 2003. The climate is favorable for the cultivation of mandarin, orange, lemon, olives, grapefruit and many other subtropical plants.