The Trivandrum Observatory or Thiruvananthapuram Astronomical Observatory is a scientific and astronomical observation station that was established by the Raja of Travancore Swathi Thirunal Rama Varma in 1836–37. Dr. Raja Rama Varma Rohani Thirunal was an established astronomer and member of the British and Canadian Astronomical Societies and a cousin of Raja Swathi Thirunal. He was also the Raja of Mavelikara Palace, a branch of the Travancore Royal family. The Raja wrote to the British Resident, Colonel James Stuart Fraser, an amateur scientist proposing the establishment of an astronomical observatory. This led to John Caldecott who earlier ran a small personal observatory at Alappuzha being appointed as the royal astronomer. The observatory was located on the highest point in the city and opposite the palace and was considered important as the magnetic equator at that time passed through Thiruvananthapuram. The observatory was designed by Lieutenant W. H. Horsley of the Madras Engineers. The British resident William Cullen initially considered the observatory as a bad use of money but the Raja and Caldecott were united in support of it.