This is a bonus cache. There is nothing at these coordinates. You will need to complete the Adventure Lab called Will & Lyra to collect the information to find the coordinates.
The Adventure Lab app can be downloaded free from the usual on-line stores and is played via smartphone.
https://labs.geocaching.com/
The coordinates and hint will be revealed as you complete each of the five Adventure labs. Make a note of the bonus numbers from each stage. Once you have seen the final page, you can go back to the opening page and open the "View Journal" section, scrolling right through each of the five pages in turn for a reminder.
In keeping with the AdLab theme, the Botanic Garden is where Will and Lyra meet each other at a special bench.
The cache can be found at
N51 45.ABC W001 14.DEF
Congrats to Rabbithen on a very rapid FTF!