Hamarikyu Garden

Hama Rikyu Garden is one of the larger city parks near where the Sumida River runs into Tokyo Bay. It is nearby the new Shiodome area. The park is not spectacular but it does have a pond, open lawn areas, and trees. The garden is mostly frequented by families and couples. There is ample area at Hama Rikyu Garden for kids to run around or for people to just lounge out on a blanket away from their apartments or on break from nearby offices at lunch time.

Since the Suido (Water) Bus stops here, it makes a good starting or ending place in conjunction with a cruise up/down the Sumida River to the Asakusa area and Sensoji Temple. Hama Rikyu Garden is also only about a kilometer away from Zojoji Temple and Tokyo Tower is just beyond the temple. So if you don't mind a bit of walking, you can combine a lot of sites into a good day of sightseeing.

Tokyo Tower - Zojoji Temple - Shiodome - Hama Rikyu Garden - Sumida River Cruise - Asakusa / Sensoji Temple (or vice versa)

Frankly, I prefer to start at Sensoji Temple in Asakusa and then head down the river. You can always drop Tokyo Tower and Zojoji Temple if you are not up to a lot of walking (or time doesn't permit) and visit them on another day.