The cache, a small camoflaged cylindrical tube, is hidden near an astronomical facility with a fascinating history . . .
The Jeremiah Horrocks Observatory was built by Preston Council thanks to the persuasive efforts of George James Gibbs, the curator of the delapidated Deepdale Observatory and President of the Preston Scientific Society (see here for fascinating info on Gibbs - Engineer, Astronomer, Inventor and Public Science Lecturer).
Some 30,000 (!) people thronged on Moor Park to witness its opening perfectly timed to coincide with a total solar eclipse on 29 June 1927 - which must have been quite an event with the new observatory in the path of totality.
Its main instrument is an 8" Thomas Cooke Refractor telescope which was originally acquired by Gibbs for the Preston Municipal (Deepdale) Observatory in 1912. It was purchased by Preston Council for £200 from the widow of a wealthy Clitheroe mill owner and thought to have been built by Thomas Cooke in 1867 - making it 146 years old!.
The Observatory now belongs to the University of Central Lancashire, and is one of the 500 synoptic weather stations around the UK that forms the climatological network of the Met Office.
Gibbs died of a stroke on 22 February 1947 and the council eventually appointed Emeritus Professor Vinicio Barocas as Director in July 1949 until he retired August 1979. During his time Professor Barocas founded the Wilfred Hall Observatory at Alston near Preston which is now the main University of Central Lancashire teaching centre for Astronomy and Astrophysics.
The Observatory is named after a brilliant and remarkable man. Born in 1618 in Toxteth, Liverpool, Jeremiah Horrocks attended Cambridge University as a SIZAR (poor Scholar) from the age 13-17 (!) but dropped out and went to live in Carr House, Much Hoole near Preston where it is thought he taught children and was a lay preacher or bible reader at St. Michael's Church. He practised 
astronomy in his spare time and entered the history books by calculating and subsequently making the first observation of a transit of Venus across the Sun for 24 November 1639. He died suddenly and mysteriously on 3 January 1641 aged just 22. See here for more information on Horrocks short but highly significant life and career.
Sadly the observatory has been closed on health and safety grounds for about 8 years and the cost of the required repairs estimated at £25,000 in 2009 mean it is unlikely to re-open soon. See here for an interesting 2009 blog article on the arguments about the future of the Observatory - a 'wasted treasure or fading relic?' and here for a local newspaper article on the call for it to be reopened.
Reaching the cache area: the nearest parking area on the park itself is over 800m away opposite Preston North End football ground on the eastern edge of the park. Otherwise you can look for somewhere closer in/on the streets to the west and south.
Replacing the cache: kindly ensure that the cache is securely replaced as found . . . and keep an eye out for those muggles!
Maintenance: the cache will be maintained by the CO SawaSawa when in Preston on periodic visits and by brother cacher ConsitonOldMan during his more frequent visits.