Problems to use relative clauses?
Click here for an explanation and plenty of exercises.
Try another exercise here.
To practise the difference between that and what click here.
For an exercise about which with prepositions, click here.
Who, whom, where and whose here and here.
When to omit the relative pronoun, here.
If you're feeling strong and full of beans, click here for lots of (rather difficult) practice.
Learn some scenery vocabulary here. Here you have words you can use to describe towns and cities. A very good interactive page from the Cambridge Dictionary here.
Here you will find more vocabulary and an exercise at the bottom of the page (not difficult, but it'll help you remember some words). This one is an interactive worksheet that includes descriptions of places. And another exercise here.
Click here to learn vocabulary with Quizlet.