Estuary Cottage - 10 Robinson Road, Whitianga

The Coromandel offers many spectacular places to go walking or hiking.  Some of the highlights are:
Kauaeranga Valley :

Located 14k inland from Thames.  This area offers numerous trails, complete with camping facilities.  Bunk house accommodation is available at the Pinnacles Hut.
Castle Rock: This strenous hike from the 309 road to the top of Castle Rock can take up to 2 hours to complete, but affords great views of the Coromandel and the Hauraki Gulf.
Kauri Grove: The 309 Kauri grove is a short walk (15 minutes) but allows you to discover Kauri trees - one of the main reasons that this area became developed.
Otama Forest: The Otama Forest walkway is just outside Kuaotunu and crosses farmland.  There is also an abandoned goldmine that has glow-worms and old mining tracks to follow.
For a fairly comprehensive list of walks in the region, take a look at the Waikato area on the Department of Conservation Website.