Using Excel IF statement with drop down list

I have a fairly simple problem but can't find a solution: I have a table with a cell that has a drop down function. The user select from that list and I want the next next cell to also be a drop down list but is dependant upon the data in the first drop down

for example

Cell A2 user selects from:

Leeds London Liverpool

In B2 the options are now restricted depending upon the data in A2

E.G - Selecting Leeds, returns second drop down of 1,2,3 or 4 Selecting London returns A, B, C, D Selecting Liverpool returns Cat, Dog, Rabbit

I was looking to use Vlookup tables with an If Statement such as

=if (A2=Leeds(VLookup, C1:C4,2)

However I am hitting an impasse.

Thanks in advance