Make no mistake, the Belum Caves are the second largest caves in the Indian subcontinent, and the longest (3229 mts) caves in the plains of India. Formed in black limestone, the caves have long passages, spacious chambers, fresh water galleries and siphons. The constant flow of underground water helped forming caves that have their deepest point at 150 feet. Engulfed in mystery, there are 16 different pathways, including the main entrance. Moreover, there are deposits of quartz in the caves. The nearest rail-head to reach Belum Caves is Tadipatri, which is 30 kms away. There are daily trains from Delhi, Mumbai, Chennai, Hyderabad, Tirupati, Kanyakumari, Thiruvananthapuram, Coimbatore and Goa, which halt at Tadipatri railway station. From Tadipatri, one can catch a bus to Belum Caves. If you feel somewhat like Indiana Jones, this one must be explored.4. Skandagiri Hillsonefivenine.comAlso known as Kalavara Durga, Skandagiri is a mountain fortress located just 70 kms from the city of Bangalore. Although much hasn't been written about the place, the gorgeous photographs suggest that it's a perfect weekend trip for people living in Karnataka. Off Bellary Road (National Highway 7 Hyderabad-Bangalore Highway), and overlooking Nandi Hills and Muddenahalli, this place guarantees a breathtaking view at an altitude of about 1350 mts.