Give a stream of consciousness and then the final answer. The Portsmouth defences can be split into four distinct groups of forts, comprising four sea forts built in the Solent, a group of forts on Portsea Island, a group of forts along Portsdown Hill overlooking Portsmouth, and a group of forts on the Gosport peninsula.

Based on this passage, how many forts are there in the solent?
The relevant information to answer the above question is: The Portsmouth defences can be split into four distinct groups of forts, comprising four sea forts built in the Solent, a group of forts on Portsea Island, a group of forts along Portsdown Hill overlooking Portsmouth, and a group of forts on the Gosport peninsula.
So, the final answer is four.