On Day 3 (August 26, 1999), the reconnaissance team took the ferry to Yalova, drove west to Bellona, and followed the coast line up to Halidere, which is to the west of Golcuk.

In Yalova, a summer resort along the southern coast of the Izmit bay, several apartment buildings collapsed, or were severely damaged (N40^o38.822’, E29^o7.503’, 8/26/99, 11:58:34)

The bottom floors of this apartment building in Yalova failed (N40^o38.845’, E29^o7.448’, 8/26/99, 12:01:06).

The apartment buildings in Yalova also underwent failure of their first floors (N40^o38.845’, E29^o7.448’, 8/26/99, 12:01:06).

In a china store located at the first floor of an undamaged bank building in Yalova, china dishes were intact on the window shelves and very few china dishes were broken on the floor. This implies that the accelerations were not large enough to break dishes since the store had probably been cleaned after the main shock (N40^o38.855’, E29^o7.45’, 8/26/99, 12:05:32).

The first floors of this apartment building in Yalova collapsed (N40^o39.08’, E29^o15.712’, 8/26/99, 13:11:25).

Along the shoreline in Yalova, many apartment buildings collapsed. The retaining wall in front of the apartment building on the right settled and shifted laterally due to the liquefaction of its foundation. However, there were no sign of lateral spread which could have damaged the building. (N40^o40.913’, E29^o21.234’, 8/26/99, 14:42:20).

The steel rebars at the connection between the reinforced concrete columns and beams of some of the apartment buildings along the shoreline of Yalova were smooth and totally insufficient (N40^o40.913’, E29^o21.234’, 8/26/99, 14:42:20)

On the beach east of Yalova, there were oil residues washed out from the oil refinery fire across Izmit bay (N40^o41.285’, E29^o34.031’, 8/26/99, 16:00:34)

The first floors of the apartment buildings on the hillside east of Yalova were damaged or collapsed. There was no evidence of slope stability problems or ground failure (N40^o41.274’, E29^o35.257’, 8/26/99, 16:23:52).

Some of the apartment buildings on the hillside east of Yalova leaned toward the sea due to the failure of their first floor (N40^o41.274’, E29^o35.257’, 8/26/99, 16:23:52).

In Halidere, an apartment building collapsed., and the waterfront spread laterally toward the Marmara Sea (N40^o42.961’, E29^o44.805’, 8/26/99, 17:33:58).

Along the shoreline in Halidere, the road and the waterfront disappeared into the Marmara sea. Some trees were left standing in the water (N40^o42.961’, E29^o44.805’, 8/26/99, 17:33:58).

Along the shoreline of Halidere, part of the sidewalk of the waterfront subsided into the sea. The restaurant in the background settled into the sea (N40^o43.064’, E29^o45.019’, 8/26/99, 18:01:02).

Most inhabitants used bottled propane gas for heating and cooking. To our knowledge there were no reported cases of fires in residential buildings ignited by gas (N40^o43.064’, E29^o45.019’, 8/26/99, 18:01:02).

In Halidere, part of the waterfront subsided into the sea and the rest spread laterally (N40^o43.064’, E29^o45.019’, 8/26/99, 18:01:02).