Hanoi's Old Quarter is a compact, walkable maze of narrow streets full of shops, street food and scooters, so expect noise and crowds. This is the best area to sample pho, bun cha and egg coffee at long-established local spots, rather than hunting for a pristine restaurant.
If you're spending the day exploring Hanoi's Old Quarter, I'd highly recommend stopping for regular water breaks. There are plenty of 7/11's and Mini Marts that sell bottled water. Public toilets are limited, so make sure to use the bathroom when you stop in at a cafe.
Street Smart tips:
If you're here with kids, I'd recommend planning to explore on foot early morning for calmer streets.
Watch your belongings (and children)
use small bills for bargains and busy food stalls and
Pick vendors with lots of locals for safer eating
Cross streets by walking steadily into the motorbike flow rather than waiting for a gap. It can be daunting at first, but it is better to move steadily than rush across.
Use Grab when you need to cover longer distances (don't try haggling with random drivers)
Bring comfortable shoes, a light rain jacket in the wet season
Parent tip: While the streets are walkable, they are not pram friendly. If you're here with little kids I'd highly recommend using a carrier to get around the area.
Bonus: If you haven't chosen where to stay in Hanoi, I'd highly recommend looking for accommodation in this area! It's close to a lot of major attractions as well as lots of options for food.