The divided highway briefly ends at the intersection of a private road named "Heffallump Road" but remains four-lanes with a center turn lane provision only to become a divided highway again at the Oldfield Golf Club and Equestrian Center.

[4] Now in Beaufort County proper once again, the highway becomes more scenic, with panoramas of marshes and surrounding islands extending for miles.

[5] Before returning to the mainland, the remains of the former drawbridge can be found on the north side of the existing bridge, and serves as a fishing pier, then a frontage road to the Broad River Boat Launching area.

[6] SC 170 is now known as Robert Smalls Parkway for approximately 5 miles (8.0 km) as it travels in a northeasterly direction across Port Royal Island.

The frontage road ends across from the intersection with SC 128, and later SC 170 intersects with US 21 and briefly becomes a divided highway at the crossing with the Spanish Moss Trail before turning straight north and finally ending at US 21 Business (US 21 Bus.)

[9][10][5] Around 1975, SC 170 was extended slightly south over an old alignment of US 17 as mainline US 17 was placed on a new bypass west of Limehouse.

[11] Its existence created a rare alternate spur, but provided a more direct routing between Bluffton and Savannah, Georgia.