Central London, where most of the popular tourist attractions are located, is generally well-policed and safe. Areas like Westminster, the City of London, and the West End have a strong police presence.
London's public transport system, including the Underground (Tube), buses, and trains, is considered safe. However, be cautious of your belongings, especially during peak hours and in crowded areas. Popular nightlife areas like Soho, Shoreditch, and Camden are generally safe but can become rowdy, especially on weekends. It's advisable to stay aware of your surroundings and avoid confrontations.
London has efficient emergency services. The emergency number is 999 or 112 for police, ambulance, and fire services. It's also a good idea to stay informed about the areas you're visiting. Some neighborhoods may be less safe, especially after dark, so seeking local advice or consulting travel advisories is wise.