Baiter or Cobbs Quay for launching, Baiter can get really busy in terms of car parking and launching and recovery plus tide issue at times, and to be honust ive seen it when busy and it looks a nightmare. Cobbs Quay better car park, easier launch and less stressfull plus you have access on site to a small shop, toilet blocks and fuel and no tide issues at all plus its interesting going doen the channel past the RNLI college, under two bridges and past Poole Quay and sunseeker, so the extra expense would be worth it in my opinion.
Pick up a decent chart map of the harbour from a chandlers as lots of places are shallow so you will need one. And top tip, look at the chart and make sure you dont cut a corner in the channel coming out of cobbs quay, have seen many people miss a specific red marker and a few seconds later get grounded for a few hours LOL (be aware of the red marker posts and dont turn by the end of one of them, turn by the red marker buoy not the end red post)
If you wanted to venture out of the harbour then studland beach is great plus there are a couple of places from studland to get some food etc and even a great pub a small walk away the Bankes Arms.
If staying in the harbour then would suggest the following, launch at cobbs quay go through into the harbour in the small boat channel heading out then take the route which goes around brownsea island and the other smaller islands, really scenic and quiet, then at a certain point head down another channel opposite brownsea island heading towards the back of the harbour and if tide is ok perhaps stop off at arne and the nice beach there, then head further into the harbour towards hamworthy and lake, head up the channel and go up the wareham river to wareham, stop by the wareham quay and have a drink or fish and chips, head back nearer hamworthy end and perhaps go across to brownsea island and drop anchor at pottery pier end for a swim and beach. Then back to cobbs via the small channel that will take you to poole quay again, will upload a map.
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