Gunung Sewu is the name for the karst

KARST

Kilometer-square Area Radio Synthesis Telescope is a Chinese telescope project to which FAST is a forerunner. KARST is a set of large spherical reflectors on karst landforms, which are bowlshaped limestone sinkholes named after the Kras region in Slovenia and Northern Italy. It will consist of...

 region of southern central Java

Java

Java is an island of Indonesia. With a population of 135 million , it is the world's most populous island, and one of the most densely populated regions in the world. It is home to 60% of Indonesia's population. The Indonesian capital city, Jakarta, is in west Java...

 that lies to the south east of Yogyakarta, south of Surakarta

Surakarta

Surakarta, also called Solo or Sala, is a city in Central Java, Indonesia of more than 520,061 people with a population density of 11,811.5 people/km2. The 44 km2 city adjoins Karanganyar Regency and Boyolali Regency to the north, Karanganyar Regency and Sukoharjo Regency to the east and...

, and is considered a very dry and poor socio-economical region in Java. It has poor rainfall compared to the volcanic mountain areas to the north and east. Administratively most of the region is part of Gunung Kidul Regency

Gunung Kidul Regency

Gunung Kidul or Kidul Mountain is the name of a regency—a well known cultural region—and the town located in the province of Yogyakarta , Indonesia. Like many regions on the island of Java, it is densely populated with roughly 1,600 people per square kilometer...

, within the Yogyakarta province.

It is a region where archaeological evidence shows very early human activity

It is very popular with cavers although foreign tourist information such as Indonesia Handbook

Indonesia Handbook

Bill Dalton's Indonesia Handbook, published by Moon Publications in California, was the main English language tourist guide book for the whole of Indonesia between the 1970s and the 1990s.- History :...

 and more recent editions of Lonely Planet

Lonely Planet

Lonely Planet is the largest travel guide book and digital media publisher in the world. The company is owned by BBC Worldwide, which bought a 75% share from the founders Maureen and Tony Wheeler in 2007 and the final 25% in February 2011...

editions about Java and Indonesia tend not to give much information about Krakal, Baron or Krukup beaches - it is usually local tour operators websites