| RHP4249 | Plan of Clyth Harbour | 1893 |
| RHP4251 | Plan of proposed fishing harbour at Latheronwheel, including section of pier | 1830 |
| RHP4252 | Plan of the harbour of Latheronwheel. | 1840 |
| RHP4253 | Plan of proposed improvements at Lybster Harbour. | 1878 |
| RHP5229/1 | Ordnance Survey 1/2500 plan (Caithness, Sheet XXXIX 9) of Dunbeath, marked to show proposed breakwater | 1892 |
| RHP5229/2-4 | Plans and sections of Dunbeath Harbour. | 1892 |
| RHP11604 | Plan continuing the intended Portenleik road from eastward of Dunrobin to Dunbeath. | 1794 |
| RHP11610 | Plan of intended road from the town of Thurso to Dunbeath, Caithness | 1797 |
| RHP11653 | Plan of proposed road from the Bridge of Wick to the Ord of Caithness | 1807-1809 |
| RHP11654 | Plan of proposed road from the Bridge of Wick to the Ord of Caithness, Latheron, Caithness. | Oct 1807 |
| RHP11664 | Plan of intended road from Dunbeath to Thurso. | 1809 |
| RHP11693 | Plan of intended road from Golspie to Dunbeath. | Late 18th century |
| RHP13130 | Sketch plan of Lybster Harbour | 1890 |
| RHP13131 | Sketch plan of Lybster Harbour: 1891. | 1891 |
| RHP13255 | Plan of Dunbeath Harbour: 1891. | 1891 |
| RHP15034 | Bound plans and sections of the Wick and Lybster Railway | 1898 |
| RHP17866 | Plans and sections (2) of the London Midland and Scottish Railway from Wick to Lybster. | 1923 |
| RHP17870 | Plan and section of the London Midland and Scottish Railway from Wick to Lybster. | 1923 |
| RHP20975 | Architectural plan and elevation of farm house and premises in Latheron | 1835 |
| RHP30853 | Volume containing 15 architectural plans, sections, elevations and site plan of Latheron Poorhouse. | 1853-1946 |
| RHP30853/1 | Architectural drawing of Latheron Poorhouse, Caithness | Aug 1854 |
| RHP30853/2 | Architectural drawing of upper floor, Latheron Poorhouse, Caithness | 10 Jun 1854 |
| RHP30853/3 | Architectural drawing of refractory wards, Latheron Poorhouse, Caithness | 1865 |
| RHP30853/4 | Architectural drawing of ground floor, Latheron Poorhouse, Caithness | Jun 1853 |
| RHP30853/5 | Plan of land near Latheron Poorhouse, Caithness | 12 May 1939 |
| RHP30853/6 | Architectural drawing of proposed mortuary at Latheron Town & County Home, Caithness | Jun 1928 |
| RHP30853/7 | Architectural drawing of Town & County Home, Latheron, Caithness | 1934 |
| RHP30853/8 | Architectural drawing of Town & County Home, Latheron, Caithness | 29 Oct 1932 |
| RHP30853/9 | Architectural drawing of proposed alterations to Town & County Home, Latheron, Caithness | Apr 1925 |
| RHP30853/10 | Architectural drawing of engine shed, Forse House | Sep 1946 |
| RHP30853/11 | Architectural drawing of Forse House, Latheron, Caithness | Jul 1946 |
| RHP30853/12 | Architectural drawing of Forse House, Latheron, Caithness | Mar 1945 |
| RHP30853/13 | Architectural drawing of Forse House, Latheron, Caithness | Jul 1946 |
| RHP30853/14 | Architectural drawing of Forse House, Latheron, Caithness | Jul 1946 |
| RHP30853/15 | Architectural drawing of Forse House, Latheron, Caithness | Jul 1946 |
| RHP30853/16 | Note concerning revision of plans of Latheron Poorhouse | 1906 |
| RHP30853/17 | Note concerning plans of Latheron Poorhouse sent to Mr Carswell | 27 Oct 1936 |
| RHP34746 | Plan of Langwell River at Langwell House. | 1865 |
| RHP36462 | Plan of Lybster Terminus. | Late 19th century |
| RHP38300 | Ordnance Survey 1/25000 plan | nd |
| RHP38303 | Ordnance Survey 1 inch map marked to show area of proposed afforestation survey. | nd |
| RHP38311/5 | L.M.S. Railway, Northern Section: Gradient profiles, stations etc | 1937 |
| RHP43595 | 1. Bound plans and sections (with gazette notice attached) of Lybster Harbour improvements. 2. Provisional order 3. Letter | 1879 |
| RHP43664 | Ordnance Survey 1/2500 plan (Caithness sheet XXIX.9) marked to show landholdings and improvement in the area of Balnabruich and Dunbeath. | [late 19th century] |
| RHP43673 | Ordnance Survey 6 inch plan marked to show proposed new and enlarged holdings, common pasture and area reserved at smithy on farm of Clyth Mains. | 1913 |
| RHP43674 | Ordnance Survey 6 inch plan marked to show proposed new and enlarged holdings on the farm of Latheronwheel Mains. | 1913 |
| RHP43677 | Ordnance Survey 6 inch plan marked to show holdings, proposed new and enlarged holdings on farm of Remeggy. | 1914 |
| RHP43680 | Ordnance Survey 1/2500 plan (Caithness sheet XXXIX.5) marked to show landholdings at Achavrole, Badnagie and Ballentink. | 1914 |
| RHP43681 | Ordnance Survey 1/2500 plan (Caithness sheet XXXIX.9) marked to show holdings in the area of Balnabruich and Dunbeath and crops in cultivation east of Dunbeath. | 1914 |
| RHP46816 | Ordnance Survey 6 inch plan (No.1) marked to show lands at Lybster and Swiney referred to in petition of Duke of Portland for authority to feu | 2 Mar 1882 |
| RHP79530 | Ordnance Survey 6 inch plan (Caithness, sheet XXII) marked to show farm boundaries: [1944 x 1954] | nd |
| RHP79531 | Ordnance Survey 6 inch plan (Caithness, sheet XXIV) marked to show farm boundaries: [1944 x 1954] | nd |
| RHP79534 | Ordnance Survey 6 inch plan (Caithness, sheet XXVII) marked to show farm boundaries: [1944 x 1954] | nd |
| RHP79535 | Ordnance Survey 6 inch plan (Caithness, sheet XXVIII) marked to show farm boundaries: [1944 x 1954] | nd |
| RHP79536 | Ordnance Survey 6 inch plan (Caithness, sheet XXIX) marked to show farm boundaries: [1944 x 1954] | nd |
| RHP79538 | Ordnance Survey 6 inch plan (Caithness, sheet XXXIA) marked to show farm boundaries: [1944 x 1954] | nd |
| RHP79539 | Ordnance Survey 6 inch plan (Caithness, sheet XXXI) marked to show farm boundaries: [1944 x 1954] | nd |
| RHP79540 | Ordnance Survey 6 inch plan (Caithness, sheet XXXII) marked to show farm boundaries: [1944 x 1954] | nd |
| RHP79541 | Ordnance Survey 6 inch plan (Caithness, sheet XXXIII) marked to show farm boundaries: [1944 x 1954] | nd |
| RHP79542 | Ordnance Survey 6 inch plan (Caithness, sheet XXXIV) marked to show farm boundaries: [1944 x 1954] | nd |
| RHP79543 | Ordnance Survey 6 inch plan (Caithness, sheet XXXVI) marked to show farm boundary: [1944 x 1954] | nd |
| RHP79544 | Ordnance Survey 6 inch plan (Caithness, sheet XXXVII) marked to show farm boundaries: [1944 x 1954] | nd |
| RHP79545 | Ordnance Survey 6 inch plan (Caithness, sheet XXXVIII) marked to show farm boundaries: [1944 x 1954] | nd |
| RHP79546 | Ordnance Survey 6 inch plan (Caithness, sheets XXXIX & XLIII) marked to show farm boundaries: [1944 x 1954] | nd |
| RHP79547 | Ordnance Survey 6 inch plan (Caithness, sheet XLI) marked to show farm boundaries: [1944 x 1954] | nd |
| RHP79548 | Ordnance Survey 6 inch plan (Caithness, sheet XLII) marked to show farm boundaries: [1944 x 1954] | nd |
| RHP79549 | Ordnance Survey 6 inch plan (Caithness, sheet XLIV & XLIVA) marked to show farm boundaries: [1944 x 1954] | nd |
| RHP83380 | Plan of Rangag, Achavanich (Achavanach) and Stemster (Stamster) | 20 Mar 1815 |
| RHP83381 | Plan (from Ordnance Survey) of estate of Forse | 1885 |
| RHP84231 | Plan of Lybster Station in connection with application by Lybster Golf Course Committee for permission to cross railway (London Midland and Scottish Railway) | [c 1923] |
| RHP84322 | Architectural plans, as existing and proposed, of station house at Lybster in connection with proposed improvements (London Midland and Scottish Railway) | [c 1923] |
| RHP93953/19 | Plan and sections of Dunbeath Harbour | 22 Apr 1948 |
| RHP93953/36 | General plan of Lybster Harbour | Aug 1954 |
| RHP93970 | Plan and section of Clyth Harbour, showing breaches in quay wall | 1896 |
| RHP94125 | Plan of proposed road between Bridge of Wick and Ord of Caithness | Oct 1807 |
| RHP143000/3/23 | Ordnance Survey 1 inch map (Sheet 110, [Latheron]) | 1877 |