In the 1900s, the causeway is built to feed the increasing demand for imports of tin, rubber and oil palm commodities. And this project is a novel and major one during that time for Malaya and Singapura. The proposed Causeway would be 1.05 km-long and 18.28m-wide, with metre-gauge railway tracks and a 7.92m-wide roadway. It would also include a lock channel that allowed the passage of small vessels, an electric lift-bridge, water pipelines and floodgates to manage the water flow of the straits. The total cost of the project was estimated at $17 million Straits dollars, and was shared among the FMS, Johor and Singapore governments.
Officially completed on 11 June 1924, the Causeway’s construction had involved more than 2,000 workers, local and European, over nearly five years and used around 1.14 million m3 of stone. The Causeway completed Singapore’s rail connection to the mainland, and enabled the rapid rise of motor transportation between Singapore and Malaya.

During the Japanese invasion of Malaya, retreating British troops set off two explosions on the Causeway on 31 January 1942. The first wrecked the lock’s lift-bridge, while the second caused a 21.33m gap in the Causeway. The pipelines carrying water to Singapore were also severed. The Japanese subsequently constructed a girder bridge over the gap before taking control of Singapore.
After Singapore’s separation from Malaysia in August 1965, the Causeway became the border connector between the two countries. Immigration checkpoints were built on both sides, with passport controls implemented on the Singaporean side from June 1967 and from September on the Malaysian side. Through these years, there are many plans and proposals of replacing the old causeway with a new bridge and has resulted in a political rift between the two countries since the early 2000s. Even right now there is still a silent tension over the straits of Johor which continue to bond and mould our relationship with Malaysia and we hope to be in a positive way.

This cache will allow you to experience the daily livelihood of people who need to travel to and fro Singapore - Johor by modes other than car and train, in attempt to exercise or escape the long grueling jams. As frequent JB goers, we have made this crossing several times. Please be prepared for some walking! Or any other ways you can think of.. :) :)
*extracted from Wikipedia :P
Note that you need to cross the border if you want to get the cache, meaning if you depart from Singapore, please clear immigration at Malaysia, vice versa. And try not to immediately try to cross the border again, maybe have a nice drink or meal on either side before coming back again! : This will save you a lot of questioning. :)
Also, please refrain from taking photo of the surroundings. You can take photo of the logsheet, but not of the buildings and structures. :P Have fun!