Complex sentence: It starts at the surface as a 50 metre round entrance and descends 183 metres into "Starlight Cave", with the long rope descent being a spectacular part of the caving experience at Harwood's.
Split into simpler sentences: It starts at the surface as a 50 metre round entrance and descends 183 metres to later on connect with "Starlight Cave". The long rope descent is considered one of the most spectacular parts of the caving experience at Harwood's.