The coordinates above are for the park gate and parking, not the cache itself. To find the cache coordinates, you need to visit various parts of the park and answer the questions below. The total walk (including back to the car park afterwards) is less than 1½ miles.
First, many thanks to the Cambridge Sports Lake Trust, who manage the park, for permission to place this cache.
Entry to the park is free, and the park is open 24 hours a day. Dogs are welcome, although they must be kept on leads until you have crossed to the north of the 13th Public Drain (a drainage river which runs through the park).
Parking costs £2, and the car park is open from 8am until early evening (the exact time depends on the time of year: look for the signs). Please do support the park by using the official parking (if you come by car) and the café.
N 52° 14.222 E 000° 09.729. Start at the Visitors' Centre, which also contains the café. a = the year the park opened.
N 52° 14.143 E 000° 09.806. There is an interesting sundial here. Looking at the month letters on the ground, what is the bottom right letter? b = the position of this letter in the alphabet, where A is 1, B is 2 etc.
N 52° 14.169 E 000° 09.944. Read the text on the war memorial. It commemorates which anniversary of the end of the war? c is the answer.
N 52° 14.457 E 000° 10.101. Two answers to collect here. What sort of fish is pictured on the sign? The number of letters in its name is d. And what sort of bird other than the tufted duck migrates here in the winter? The number of letters in its name is e.
N 52° 14.383 E 000° 09.902. The final clue. According to the sign, what is the first thing you can find at the Visitors' Centre? h = the number of letters in this word.
The cache can now be found as follows.
Multiply b, d and (h - 2) to get a three-digit number NNN.
Take a - c - e - 1000 to get a three-digit number EEE.
The final cache is at N 52° 14.NNN E 000° 09.EEE. You are looking for a 3½ litre box, so there's plenty of room for swaps and travel bugs.