Sunday Walk: Blackheath to Greenwich or Canary Wharf

Length 12 km (7.5 miles).
This walk crosses Blackheath then takes a circuitous route through Greenwich  Park – up, down, and all around . There are fine views down to the river from the higher points. You eventually descend to historic Greenwich. You could finish the walk there but - get this - the full walk continues under the Thames via a foot tunnel and makes its way along the far bank to Canary Wharf.
Trains
Meet at 10:37 Blackheath station.
The 10:16 Dartford train from Charing Cross ( London Bridge 10:25) arrivies Blackheath at 10:37.
The 10:04 Dartford train from Victoria arrives Blackheath at 10:28.
Returning, Canary Wharf is on the Jubilee Line.
(If finishing at Greenwich, note that there's no direct DLR train from Cutty Sark to Bank today. You can still take one to Canary Wharf for the Jubilee Line. Check here for other options).
All travel is within zones 1- 3.
Elevenses Shortly after entering Greenwich Park, you encounter the Pavillion Cafe, which is quite nice but not compulsory.
Lunch The following are suggested. The Plume of Feathers (020-8858 1661) at 19 Park Vista (just outside Park Row Gate),  also The Trafalgar and The Cutty Sark (it's a pub).
Tea No particular recommendation but Canary Wharf is not short of places This guide may help. 
Places of Interest 
The National Maritime Museum, and especially the adjoining Queens House with its tulip staircase and Tudor portraits. Free to visit. Booking advised.
The Royal Naval College’s ornate chapel is worth a quick look.(free) The college’s famous Painted Hall costs £12.50 book in advance.
To go inside the Cutty Sark (it’s a ship) would set you back a few bob (£15 book in advance) but you can see the outside for nowt. 
The Royal Observatory is closed at present but keep your eye out for the time-ball descending (every day at 1pm).
Sadly, no Canary Wharf Lights festival this year cos of you-know-what. There's other stuff you can look at listed here.
Directions: here
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