Welcome to London

Read the poster. Where can you find it?
1. in a travel guide
2. in a scientific magazine
3. in a library
4. in a compilation of poems
2. What we can't learn from the poster:
- the current official name of Big Ben
- the average temperature in London
- the number of cabs in London
- the number of underground river in London
- the prices in museums
- the names of the biggest shops in London
- the system of education